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In this article, I describe the belief system at the centre of Mau and Dan mask spirit performances and some implications of these beliefs in practice, and I suggest an ontological framework for interpreting the ambiguous agency embodied in such performances. I ground my discussion of this ontological framework by juxtaposing ethnographic material about non-commercial, community-based mask spirit belief and practice with details of the career of an international ‘star’ mask spirit performer, Vado Diomande. I propose that the ambiguous agency at the heart of these performances is best understood using a performance framework that locates being in process. My interlocutors’ discourse about and practices of these performances suggest that, rather than looking for ontology in performance, we understand ontology as performance – or perhaps better yet, performance as ontology. Such a framework illuminates both the challenges and the strategic advantages that ontological ambiguity presents to mask spirit performers in immigrant settings in the US. This framework also provides a philosophical grounding for theories positing African art as process, and sheds light on the ways in which mask spirit performers manoeuvre in the interstices of display and disguise, addressing both belief and market demand.
Use of ketamine in the prehospital setting may be advantageous due to its potent analgesic and sedative properties and favorable risk profile. Use in the military setting has demonstrated both efficacy and safety for pain relief. The purpose of this study was to assess ketamine training, use, and perceptions in the civilian setting among nationally certified paramedics (NRPs) in the United States.
A cross-sectional survey of NRPs was performed. The electronic questionnaire assessed paramedic training, authorization, use, and perceptions of ketamine. Included in the analysis were completed surveys of paramedics who held one or more state paramedic credentials, indicated “patient care provider” as their primary role, and worked in non-military settings. Descriptive statistics were calculated.
A total of 14,739 responses were obtained (response rate=23%), of which 10,737 (73%) met inclusion criteria and constituted the study cohort. Over one-half (53%) of paramedics reported learning about ketamine during their initial paramedic training. Meanwhile, 42% reported seeking ketamine-related education on their own. Of all respondents, only 33% (3,421/10,737) were authorized by protocol to use ketamine. Most commonly authorized uses included pain management (55%), rapid sequence intubation (RSI; 72%), and chemical restraint/sedation (72%). One-third of authorized providers (1,107/3,350) had never administered ketamine, with another 32% (1,070/3,350) having administered ketamine less than five times in their career. Ketamine was perceived to be safe and effective as the vast majority reported that they were comfortable with the use of ketamine (94%) and would, in similar situations (95%), use it again.
This was the first large, national survey to assess ketamine training, use, and perceptions among paramedics in the civilian prehospital setting. While training related to ketamine use was commonly reported among paramedics, few were authorized to administer the drug by their agency’s protocols. Of those authorized to use ketamine, most paramedics had limited experience administering the drug. Future research is needed to determine why the prevalence of ketamine use is low and to assess the safety and efficacy of ketamine use in the prehospital setting.
BucklandDM, CroweRP, CashRE, GondekS, MalusoP, SirajuddinS, SmithER, DangerfieldP, ShapiroG, WankaC, PanchalAR, SaraniB. Ketamine in the Prehospital Environment: A National Survey of Paramedics in the United States. Prehosp Disaster Med. 2018;33(1):23–28.
This paper is concerned with how urban food activists related to the media during 2015, when Bristol was the European Green Capital (EGC), how they represented themselves and how others represented their agenda. Our intention is to inform the debates on urban agriculture (UA) and, more specifically, to contribute to discussions about ‘scaling up’ UA. To achieve this, we adopt a form of analysis that rests on Castells’ insights about contemporary protest movements, the media and the role of communication technologies in constituting social power. By using Bristol, a city with a well-developed and studied urban agriculture movement, we suggest new areas for consideration that focus on the importance of communication in the development of the movement. Our study relied only on publicly available data; newspaper reports about the EGC and a sample of the social media used by the urban food networks in the city. We found that the mass media was mainly concerned with reporting topics other than food and that urban food was not a salient issue in their coverage. The Twitter network we analyzed was a loose constellation of different communities, which shared materials that were mostly concerned with creating a shared, normative picture of urban food. By considering the structure of these forms of media, we can observe the assembly of the forms of communication and their content. The paper concludes that the self-representation of urban food networks at that time reveals a narrow focus of interest. This emphasis may have contributed to the lack of connection within the city between potential allies. Our conclusion supports similar research findings in neighboring communities, which have observed the limited connections of urban food networks to the circuits of power and influence.
A clean hot-water drill was used to gain access to Subglacial Lake Whillans (SLW) in late January 2013 as part of the Whillans Ice Stream Subglacial Access Research Drilling (WISSARD) project. Over 3 days, we deployed an array of scientific tools through the SLW borehole: a downhole camera, a conductivity–temperature–depth (CTD) probe, a Niskin water sampler, an in situ filtration unit, three different sediment corers, a geothermal probe and a geophysical sensor string. Our observations confirm the existence of a subglacial water reservoir whose presence was previously inferred from satellite altimetry and surface geophysics. Subglacial water is about two orders of magnitude less saline than sea water (0.37–0.41 psu vs 35 psu) and two orders of magnitude more saline than pure drill meltwater (<0.002 psu). It reaches a minimum temperature of –0.55~C, consistent with depression of the freezing point by 7.019 MPa of water pressure. Subglacial water was turbid and remained turbid following filtration through 0.45 µm filters. The recovered sediment cores, which sampled down to 0.8 m below the lake bottom, contained a macroscopically structureless diamicton with shear strength between 2 and 6 kPa. Our main operational recommendation for future subglacial access through water-filled boreholes is to supply enough heat to the top of the borehole to keep it from freezing.
This paper presents a method for automatically generating new designs from a set of existing objects of the same class using machine learning. In this particular work, we use a custom parametric chair design program to produce a large set of chairs that are tested for their physical properties using ergonomic simulations. Design schemata are found from this set of chairs and used to generate new designs by placing constraints on the generating parameters used in the program. The schemata are found by training decision trees on the chair data sets. These are automatically reverse engineered by examining the structure of the trees and creating a schema for each positive leaf. By finding a range of schemata, rather than a single solution, we maintain a diverse design space. This paper also describes how schemata for different properties can be combined to generate new designs that possess all properties required in a design brief. The method is shown to consistently produce viable designs, covering a large range of our design space, and demonstrates a significant time saving over generate and test using the same program and simulations.
Investigations on the relationship between sweet taste perception and body mass index (BMI) have been inconclusive. Here, we report a longitudinal analysis using a genetically informative sample of 1,576 adolescent Australian twins to explore the relationship between BMI and sweet taste. First, we estimated the phenotypic correlations between perception scores for four different sweet compounds (glucose, fructose, neohesperidine dihydrochalcone (NHDC), and aspartame) and BMI. Then, we computed the association between adolescent taste perception and BMI in early adulthood (reported 9 years later). Finally, we used twin modeling and polygenic risk prediction analysis to investigate the genetic overlap between BMI and sweet taste perception. Our findings revealed that BMI in early adulthood was significantly associated with each of the sweet perception scores, with the strongest correlation observed in aspartame with r = 0.09 (p = .007). However, only limited evidence of association was observed between sweet taste perception and BMI that was measured at the same time (in adolescence), with the strongest evidence of association observed for glucose with a correlation coefficient of r = 0.06 (p = .029) and for aspartame with r = 0.06 (p = .035). We found a significant (p < .05) genetic correlation between glucose and NHDC perception and BMI. Our analyses suggest that sweet taste perception in adolescence can be a potential indicator of BMI in early adulthood. This association is further supported by evidence of genetic overlap between the traits, suggesting that some BMI genes may be acting through biological pathways of taste perception.
The perception of sweetness varies among individuals but the sources of this variation are not fully understood. Here, in a sample of 1,901 adolescent and young adults (53.8% female; 243 MZ and 452 DZ twin pairs, 511 unpaired individuals; mean age 16.2 ± 2.8, range 12–26 years), we studied the variation in the perception of sweetness intensity of two monosaccharides and two high-potency sweeteners: glucose, fructose, neohesperidine dihydrochalcone (NHDC), and aspartame. Perceived intensity for all sweeteners decreased with age (2–5% per year) and increased with the history of otitis media (6–9%). Males rated aspartame slightly stronger than females (7%). We found similar heritabilities for sugars (glucose: h2 = 0.31, fructose: h2 = 0.34) and high-potency sweeteners (NHDC: h2 = 0.31, aspartame: h2 = 0.30); all were in the modest range. Multivariate modeling showed that a common genetic factor accounted for >75% of the genetic variance in the four sweeteners, suggesting that individual differences in perceived sweet intensity, which are partly due to genetic factors, may be attributed to a single set of genes. This study provided evidence of the shared genetic pathways between the perception of sugars and high-potency sweeteners.
The reaction mechanism of BaCO3+CaCO3+TiO2 by solid state methods has been studied in this work using thermal analysis (DSC-TG) from 500 to 1500 °C and in situ X-ray diffraction (XRD) from room temperature to 800 °C. In the mixed powders, the CaO is firstly formed followed by presence of an intermediate Ba2TiO4 phase and finally the formation of CaTiO3, BaTiO3 and/or (Ba,Ca)TiO3, where the presence of CaO or CaTiO3 (CT) has slowed down the formation of BaTiO3 (BT). Raman microscopy of a BT-CT diffusion couple has shown that Ca2+ firstly diffuses into the BT grain boundaries and then into the BT core.
This research reevaluates the effect of the Australian ballot reforms of the late nineteenth century on voter mobilization and turnout, challenging the “vote market hypothesis” regarding voter bribery by political parties. We propose that any subsequent declines in turnout were more directly affected by ballot design than by voter secrecy. In a regression analysis of voter turnout in statewide gubernatorial elections from 1870 to 1910, we find a significant decline in turnout in those states implementing “office bloc” reform ballots. However, the use of “party column” reform ballots did not lead to a decline in turnout. The results suggest that secrecy in voting does not fully explain the national turnout decline observed after passage.
The need to understand fast, complex physical phenomena through direct in
situ observation has spurred the development of
high-time-resolution transmission electron microscopy (TEM). Two complementary
approaches have emerged: the single-shot and stroboscopic techniques.
Single-shot TEM has advanced through the development of dynamic transmission
electron microscopy (DTEM) and, more recently, by the advent of movie-mode DTEM,
which enables high-frame-rate in situ TEM experimentation by
capturing nanosecond-scale sequences of images or diffraction patterns. Previous
DTEM studies produced only single snapshots of fast material processes.
Movie-mode DTEM provides the ability to track the creation, motion, and
interaction of individual defects, phase fronts, and chemical reaction fronts,
providing invaluable information on the chemical, microstructural, and
atomic-level features that govern rapid material processes. This article
discusses movie-mode DTEM technology, its application in the study of reaction
dynamics in Ti–B-based reactive nanolaminates, and future