7,951 research outputs found
Performative Rituals for Conception and Childbirth in England, 900-1500.
This study proposes that performative rituals-that is, verbal and physical acts that reiterate prior uses-enabled medieval women and men to negotiate the dangers and difficulties of conception and childbirth. It analyzes the rituals implicated in charms, prayers, amulets, and prayer rolls and traces the circulation of such rituals within medieval English society. Manuscript records from the Anglo-Saxon period to the late Middle Ages offer evidence of the interaction of oral and written means of communicating these rituals. Certain rituals were long-lived, though variants were introduced over time that reflected changing religious attitudes and the involvement of various interested parties, including local healers, doctors, and medical practitioners, as well as monks, friars, and users of vernacular remedy books. Although many of those who recommended or provided assistance through performative rituals were males, the practices often devolved upon women themselves, and their female companions or attendants.This research was supported by Wellcome Trust grant 088708.This is the final version of the article. It first appeared from Johns Hopkins University Press via http://dx.doi.org/10.1353/bhm.2015.007
Organic Carbon Emissions from the Co-firing of Coal and Wood in a Fixed Bed Combustor
Co-firing of biomass and coal and biomass reduces the emission of pollutants and the overall effects have been extensively studied, but many aspects of the detailed mechanism remain uncertain. A number of studies have been previously made by us of emissions from the combustion in a fixed-bed furnace of bituminous coal and wood, both individually and together, and it was observed that biomass produced less soot and lower NOX emissions. These data are combined with recent measurements of emissions of black carbon (BC) and organic carbon (OC), which are an important source of climate forcing, from the combustion of a number of solid fuels. Conclusion are drawn about the nature of the OC and how the values are dependent on the measurement technique used. Complementary analytical-scale combustion and pyrolysis experiments were also carried out. The results of the analysis of emissions and reaction products, mainly by gas chromatography–mass spectrometry (GC–MS), were interpreted so as to construct a model for pollutant formation during co-firing
Mindfulness-based exposure and response prevention for obsessive compulsive disorder: study protocol for a pilot randomised controlled trial
Background
Obsessive Compulsive Disorder (OCD) is a distressing and debilitating condition affecting 1-2% of the population. Exposure and response prevention (ERP) is a behaviour therapy for OCD with the strongest evidence for effectiveness of any psychological therapy for the condition. Even so, only about half of people offered ERP show recovery after the therapy. An important reason for ERP failure is that about 25% of people drop out early, and even for those who continue with the therapy, many do not regularly engage in ERP tasks, an essential element of ERP. A mindfulness-based approach has the potential to reduce drop-out from ERP and to improve ERP task engagement with an emphasis on accepting difficult thoughts, feelings and bodily sessions and on becoming more aware of urges, rather than automatically acting on them.
Methods/Design
This is a pilot randomised controlled trial of mindfulness-based ERP (MB-ERP) with the aim of establishing parameters for a definitive trial. Forty participants diagnosed with OCD will be allocated at random to a 10-session ERP group or to a 10-session MB-ERP group. Primary outcomes are OCD symptom severity and therapy engagement. Secondary outcomes are depressive symptom severity, wellbeing and obsessive-compulsive beliefs. A semi-structured interview with participants will guide understanding of change processes.
Discussion
Findings from this pilot study will inform future research in this area, and if effect sizes on primary outcomes are in favour of MB-ERP in comparison to ERP, funding for a definitive trial will be sought
Sulfur isotope values in the sulfidic Frasassi cave system, central Italy : a case study of a chemolithotrophic S-based ecosystem
This work was supported by NASA Exobiology (NNX07AV54G) (A.Z. and J.F.), a Natural Environment Research Council Fellowship (NE/H016805) (A.Z.), the National Science Foundation (NSF EAR-0525503 and EAR-1124411) (J.M.), and the NASA Astrobiology Institute (PSARC, NNA04CC06A) (J.M.).Sulfide oxidation forms a critical step in the global sulfur cycle, although this process is notoriously difficult to constrain due to the multiple pathways and highly reactive intermediates involved. Multiple sulfur isotopes (δ34S and Δ33S) can provide a powerful tool for unravelling sulfur cycling processes in modern (and ancient) environments, although they have had limited application to systems with well-resolved oxidative S cycling. In this study, we report the major (δ34S) and minor (Δ33S) isotope values of sulfur compounds in streams and sediments from the sulfidic Frasassi cave system, Marche Region, Italy. These microaerophilic cave streams host prominent white biofilms dominated by chemolithotrophic organisms that oxidize sulfide to S0, allowing us to estimate S isotope fractionations associated with in situ sulfide oxidation and to evaluate any resulting isotope biosignatures. Our results demonstrate that chemolithotrophic sulfide oxidation produces 34S enrichments in the S0 products that are larger than those previously measured in laboratory experiments, with 34ɛS0-H2S of up to 8‰ calculated. These small reverse isotope effects are similar to those produced during phototrophic sulfide oxidation (≤ 7‰), but distinct from the small normal isotope effects previously calculated for abiotic oxidation of sulfide with O2 (~-5‰). An inverse correlation between the magnitude of 34ɛS0-H2S effects and sulfide availability, along with substantial differences in Δ33S, both support complex sulfide oxidation pathways and intracellular recycling of S intermediates by organisms inhabiting the biofilms. At the ecosystem level, we calculate fractionations of less than 40‰ between sulfide and sulfate in the water column and in the sediments. These fractionations are smaller than those typically calculated for systems dominated by sulfate reduction (> 50‰), and contrast with the commonly held assumption that oxidative recycling of sulfide generally increases overall fractionations. The relatively small fractionations appear to be related to the sequestration of S0 in the biofilms (either intra- or extra-cellularly), which removes this intermediate substrate from fractionation by further disproportionation or oxidation reactions. In addition, the net 33λH2S-SO4 values calculated in this system are larger than data published for systems dominated by reductive sulfur cycling, partially due to the isotopic imprint of chemolithotrophic sulfide oxidation on the aqueous sulfide pool. These distinct isotopic relationships are retained in the sedimentary sulfur pool, suggesting that trends in 34S and 33S isotope values could provide an isotopic fingerprint of such chemolithotrophic ecosystems in modern and ancient environments.PostprintPeer reviewe
Detection of Planetary and Stellar Companions to Neighboring Stars via a Combination of Radial Velocity and Direct Imaging Techniques
13 pages, 6 figures, 4 tables, accepted for publication in the Astronomical Journal (submitted 25 Feb 2019; accepted 28 April 2019). Machine readable tables and Posteriors from the RadVel fits are available here: http://stephenkane.net/rvfits.tarThe sensitivities of radial velocity (RV) surveys for exoplanet detection are extending to increasingly longer orbital periods, where companions with periods of several years are now being regularly discovered. Companions with orbital periods that exceed the duration of the survey manifest in the data as an incomplete orbit or linear trend, a feature that can either present as the sole detectable companion to the host star, or as an additional signal overlain on the signatures of previously discovered companion(s). A diagnostic that can confirm or constrain scenarios in which the trend is caused by an unseen stellar rather than planetary companion is the use of high-contrast imaging observations. Here, we present RV data from the Anglo-Australian Planet Search (AAPS) for 20 stars that show evidence of orbiting companions. Of these, six companions have resolved orbits, with three that lie in the planetary regime. Two of these (HD 92987b and HD 221420b) are new discoveries. Follow-up observations using the Differential Speckle Survey Instrument (DSSI) on the Gemini South telescope revealed that 5 of the 20 monitored companions are likely stellar in nature. We use the sensitivity of the AAPS and DSSI data to place constraints on the mass of the companions for the remaining systems. Our analysis shows that a planetary-mass companion provides the most likely self-consistent explanation of the data for many of the remaining systems.Peer reviewedFinal Accepted Versio
Data Safe Havens and Trust: Toward a Common Understanding of Trusted Research Platforms for Governing Secure and Ethical Health Research
In parallel with the advances in big data-driven clinical research, the data safe haven concept has evolved over the last decade. It has led to the development of a framework to support the secure handling of health care information used for clinical research that balances compliance with legal and regulatory controls and ethical requirements while engaging with the public as a partner in its governance. We describe the evolution of 4 separately developed clinical research platforms into services throughout the United Kingdom-wide Farr Institute and their common deployment features in practice. The Farr Institute is a case study from which we propose a common definition of data safe havens as trusted platforms for clinical academic research. We use this common definition to discuss the challenges and dilemmas faced by the clinical academic research community, to help promote a consistent understanding of them and how they might best be handled in practice. We conclude by questioning whether the common definition represents a safe and trustworthy model for conducting clinical research that can stand the test of time and ongoing technical advances while paying heed to evolving public and professional concerns
Ignition Risks of Biomass Dust on Hot Surfaces
Combustible biomass dusts are formed at various handling stages, and accumulations of these dusts can occur on hot surfaces of electrical and mechanical devices and can pose fire risks. This study evaluates the ignition characteristics of dust from two types of biomass commonly used in the U.K. power stations: herbaceous miscanthus and woody pine. The ignition risks of the individual biomass and their blends in two different weight ratios, 90 wt % pine to 10 wt % miscanthus and 50 wt % pine to 50 wt % miscanthus, were investigated. Biomass–biomass blends represent the power plant scenario where a number of biomass are fired under daily operation, and thus, dust sedimentation could consist of material blends. The influence of washing pretreatment (particularly to remove catalytic potassium) on the ignition behavior of these dusts was investigated. Fuel characterization via proximate and ultimate analyses was performed on all fuels and combustion characteristics via thermogravimetric analysis (TGA). The risk of self-ignition propensity of both untreated and washed biomass was ranked graphically using the activation energy (Ea) for combustion and the temperature of maximum weight loss (TMWL) determined from the derivative TGA (DTG) curve. It was found that the TMWL and Ea of washed biomass were higher than those of the untreated biomass, implying a lower self-ignition risk. Similar analyses were performed on untreated and washed blends, and comparable results were observed. The ignition characteristics were studied following the British Standard test methods for determining the minimum ignition temperature of a 5 mm dust layer on a heated surface. It was found that the washed individual biomass and their blends revealed slightly higher dust ignition temperatures than their respective untreated counterparts, a 20 and 10 °C difference for individual biomass and blends, respectively. The effect of washing on the ignition delay time was more obvious for pine than for miscanthus, but the time difference between the untreated and washed biomass never exceeded 4 min for all biomass and blends. The biomass pretreatment method of washing did change the combustion and self-ignition characteristics of biomass dust, and there was evidence of potassium being leached from the fuels upon washing (particularly miscanthus). This is considered the main reason for the increase in the minimum ignition temperature. While the washed biomass is found to have a lower ignition risk, it should be noted that the result (validated for up to 5 mm thickness) is not significant enough to influence plant operations for the ignition risk from thin dust layers according to the National Fire Protection Association (NFPA) standard
The future of enterprise groupware applications
This paper provides a review of groupware technology and products. The purpose of this review is to investigate the appropriateness of current groupware technology as the basis for future enterprise systems and evaluate its role in realising, the currently emerging, Virtual Enterprise model for business organisation. It also identifies in which way current technological phenomena will transform groupware technology and will drive the development of the enterprise systems of the future
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