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The Universe is permeated by hot, turbulent, magnetized plasmas. Turbulent plasma is a major constituent of active galactic nuclei, supernova remnants, the intergalactic and interstellar medium, the solar corona, the solar wind and the Earth’s magnetosphere, just to mention a few examples. Energy dissipation of turbulent fluctuations plays a key role in plasma heating and energization, yet we still do not understand the underlying physical mechanisms involved. THOR is a mission designed to answer the questions of how turbulent plasma is heated and particles accelerated, how the dissipated energy is partitioned and how dissipation operates in different regimes of turbulence. THOR is a single-spacecraft mission with an orbit tuned to maximize data return from regions in near-Earth space – magnetosheath, shock, foreshock and pristine solar wind – featuring different kinds of turbulence. Here we summarize the THOR proposal submitted on 15 January 2015 to the ‘Call for a Medium-size mission opportunity in ESAs Science Programme for a launch in 2025 (M4)’. THOR has been selected by European Space Agency (ESA) for the study phase.
Few countries routinely collect comprehensive encephalitis data, yet understanding the epidemiology of this condition has value for clinical management, detecting novel and emerging pathogens, and guiding timely public health interventions. When this study was conducted there was no standardized diagnostic algorithm to aid identification of encephalitis or systematic surveillance for adult encephalitis. In July 2012 we tested three pragmatic surveillance options aimed at identifying possible adult encephalitis cases admitted to a major Australian hospital: hospital admissions searches, clinician notifications and laboratory test alerts (CSF herpes simplex virus requests). Eligible cases underwent structured laboratory investigation and a specialist panel arbitrated on the final diagnosis. One hundred and thirteen patients were initially recruited into the 10-month study; 20/113 (18%) met the study case definition, seven were diagnosed with infectious or immune-mediated encephalitis and the remainder were assigned alternative diagnoses. The laboratory alert identified 90% (102/113) of recruited cases including six of the seven cases of confirmed encephalitis suggesting that this may be a practical data source for case ascertainment. The application of a standardized diagnostic algorithm and specialist review by an expert clinical panel aided diagnosis of patients with encephalitis.
1.1 This paper owes its existence on two counts to the late Jim Souness whose term of office as President of the Faculty coincided with the bulk of our research. Firstly, as President, he encouraged Faculty research groups to be active and to produce material worthy of sessional papers. More directly it was the late President who funnelled our general investigations of life office management (which had continued after the Group's 1987 sessional paper) towards the issue of demutualisation.
There have been several notable demutualisations of life offices in recent years, yet there is little published research in the UK other than case studies into the actuarial issues which these restructurings raise for the profession. Furthermore much of what has been published pertains to overseas regimes not subject to UK-style regulation. However at the time of writing we are aware that another paper (reference 20) was being written concurrently, and it relates specifically to the UK.
1.1.1 The Bonus and Valuation Research Group of the Faculty of Actuaries began the work which eventually led to this paper towards the end of 1991. About this time there was considerable speculation that levels of maturity payouts on with profits policies might be significantly in excess of the level that could be justified by the actual investment earnings underlying the policies. The initial aims of the research group were to:
(a) examine this claim;
(b) consider to what extent overpayment, if any, could be explained by the smoothing methods that might have been used by offices; and
(c) examine the practical consequences of continuing to adopt those smoothing methods.
We relate the geometric Poisson brackets on the 2-Grassmannian in ℝ4 and on the (2, 2) Möbius sphere. We show that, when written in terms of local moving frames, the geometric Poisson bracket on the Möbius sphere does not restrict to the space of differential invariants of Schwarzian type. But when the concept of conformal natural frame is transported from the conformal sphere into the Grassmannian, and the Poisson bracket is written in terms of the Grassmannian natural frame, it restricts and results in either a decoupled system or a complexly coupled system of Korteweg–de Vries (KdV) equations, depending on the character of the invariants. We also show that the bi-Hamiltonian Grassmannian geometric brackets are equivalent to the non-commutative KdV bi-Hamiltonian structure. Both integrable systems and Hamiltonian structure can be brought back to the conformal sphere.
A verified instrumental calibration of annually resolved δ18O for a stalagmite from Gümüşhane in northeast Turkey is presented and cross-validated using a ‘leave-one-out’ technique. The amount of late autumn to winter precipitation is negatively correlated with stalagmite δ18O between AD 1938 and 2004. The observed relationship is extrapolated back to ~ AD 1500 leading to the first long winter precipitation reconstruction for this region. Modern day October to January precipitation is linked to pressure fields in Western Russia. Anomalously lower reconstructed rainfall is recorded in AD 1540–1560 at which time higher pressure over the Caspian Sea region is inferred.
In this paper we describe Fourier transform Photoluminescence (FTPL) spectroscopy and report the first application of this technique to the analysis of semiconductor silicon. Two applications of FTPL spectroscopy to silicon are discussed. The first application is to quantitative trace analysis of the Ill-V impurities B,P, As and Al in silicon. Both high purity and compensated silicon have been studied and PL features correlated to the concentrations of the individual impurity species present. The capability of analysing B, P, As and Al at part per trillion atomic concentrations in silicon is demonstrated. In the second part of this paper, application of FTPL to the analysis of thermally induced microdefects in silicon is discussed. Defect band intensities are shown to be proportional to the concentration of interstitial oxygen precipitated in the case of plate precipitate morphology. In these two applications, FTPL is shown to uniquely provide both residual impurity and microdefect information of as grown and processed silicon.
Studies suggest that neuronal density in left dorsolateral prefrontal
cortex is increased in schizophrenia.
To replicate these findings and extend them to both hemispheres.
Neuronal density, size and shape were estimated in the prefrontal cortex
(Brodmann area 9) of the left and right hemispheres of brains taken
postmortem from 10 people with schizophrenia and 10 without mental
illness (6 men, 4 women in both groups).
Overall neuronal density (individually corrected for shrinkage) did not
differ between the groups. In the control brains, density was generally
greater in the left than the right hemisphere, the reverse was seen in
the schizophrenia brains; this loss or reversal of asymmetry was most
significant in cortical layer 3. Pyramidal neurons in this cell layer
were significantly larger on the left and more spherical in shape than on
the right side in control brains, but size and shape did not differ
between the two sides in schizophrenia. Non-pyramidal and glial cell
densities were unchanged.
We failed to find an increase in neuronal density, but found evidence at
a cellular level of loss or reversal of asymmetry, consistent with the
hypothesis of a primary change in the relative development of areas of
heteromodal association cortex in the two hemispheres.
Central venous catheter (CVC)-related bloodstream infections (BSIs) are known to increase rates of morbidity and mortality in both inpatients and outpatients, including hematology-oncology patients and those undergoing hemodialysis or home infusion therapy. Biofilm-associated organisms on the lumens of these catheters have reduced susceptibility to antimicrobial chemotherapy. This study tested the efficacy of tetrasodium EDTA as a catheter lock solution on biofilms of several clinically relevant microorganisms.
Biofilms of Staphylococcus epidermidis, methicillin-resistant S. aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Candida albicans were grown to levels of approximately 1 × 105 colony-forming units (CFU)/cm−1 on CVC segments in a model system, then subjected to the tetrasodium EDTA lock treatment.
Comparisons of biofilms before and after exposure to the 40-mg/mL−1 tetrasodium EDTA lock for 21 hours showed that the biofilm viable cell counts of all organisms tested were significantly reduced (P < .05) after exposure to the treatment.
Antimicrobial lock treatment using 40 mg/mL−1 of tetrasodium EDTA for at least 21 hours could significantly reduce or potentially eradicate CVC-associated bio-films of clinically relevant microorganisms (Infect Control Hosp Epidemiol 2005;26:515-519).
Fungi play a key role in ecosystem nutrient cycles by scavenging, concentrating, translocating and redistributing nitrogen. To quantify and predict fungal nitrogen redistribution, and assess the importance of the integrity of fungal networks in soil for ecosystem function, we need better understanding of the structures and processes involved. Until recently nitrogen translocation has been experimentally intractable owing to the lack of a suitable radioisotope tracer for nitrogen, and the impossibility of observing nitrogen translocation in real time under realistic conditions. We have developed an imaging method for recording the magnitude and direction of amino acid flow through the whole mycelial network as it captures, assimilates and channels its carbon and nitrogen resources, while growing in realistically heterogeneous soil microcosms. Computer analysis and modeling, based on these digitized video records, can reveal patterns in transport that suggest experimentally testable hypotheses. Experimental approaches that we are developing include genomics and stable isotope NMR to investigate where in the system nitrogen compounds are being acquired and stored, and where they are mobilized for transport or broken down. The results are elucidating the interplay between environment, metabolism, and the development and function of transport networks as mycelium forages in soil. The highly adapted and selected foraging networks of fungi may illuminate fundamental principles applicable to other supply networks.
We tested the efficacy and safety of linopirdine, a novel phenylindolinone, in the treatment of Alzheimer's disease.
A multicentre, randomized, double-blind, parallel group, placebo-controlled trial of linopirdine (30 mg three times per day or placebo). Patients (n = 382, 55% male, 98% Caucasian, age range 51-95 years) with mild or moderate Alzheimer's disease, of whom 375 received at least one treatment dose were analysed. There were no important differences between the groups at baseline.
No difference was seen in Clinical Global Impression scores between patients receiving placebo and those receiving linopirdine (n = 189). Small differences in the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) scores were seen throughout the study favouring linopirdine; at 6 months the ADAS-Cog scores were 20.2 (linopirdine) and 22.1 (placebo) p = 0.01.
This trial did not detect clinically meaningful differences in patients receiving linopirdine for 6 months, despite evidence of a small degree of improved cognitive function. Further studies may benefit from more sensitive tests of treatment effects in Alzheimer's disease.