An inhibitory effect of D-Mannoheptulose on lactate formation in human whole blood in vitro

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Effects of electrojet turbulence on a magnetosphere-ionosphere simulation of a geomagnetic storm

Ionospheric conductance plays an important role in regulating the response of the magnetosphere‐ionosphere system to solar wind driving. Typically, models of magnetosphere‐ionosphere coupling include changes to ionospheric conductance driven by extreme ultraviolet ionization and electron precipitation. This paper shows that effects driven by the Farley‐Buneman instability can also create significant enhancements in the ionospheric conductance, with substantial impacts on geospace. We have implemented a method of including electrojet turbulence (ET) effects into the ionospheric conductance model utilized within geospace simulations. Our particular implementation is tested with simulations of the Lyon‐Fedder‐Mobarry global magnetosphere model coupled with the Rice Convection Model of the inner magnetosphere. We examine the impact of including ET‐modified conductances in a case study of the geomagnetic storm of 17 March 2013. Simulations with ET show a 13% reduction in the cross polar cap potential at the beginning of the storm and up to 20% increases in the Pedersen and Hall conductance. These simulation results show better agreement with Defense Meteorological Satellite Program observations, including capturing features of subauroral polarization streams. The field‐aligned current (FAC) patterns show little differences during the peak of storm and agree well with Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) reconstructions. Typically, the simulated FAC densities are stronger and at slightly higher latitudes than shown by AMPERE. The inner magnetospheric pressures derived from Tsyganenko‐Sitnov empirical magnetic field model show that the inclusion of the ET effects increases the peak pressure and brings the results into better agreement with the empirical model.This material is based upon work supported by NASA grants NNX14AI13G, NNX13AF92G, and NNX16AB80G. The National Center for Atmospheric Research is sponsored by the National Science Foundation. This work used the XSEDE and TACC computational facilities, supported by National Science Foundation grant ACI-1053575. We would like to acknowledge high-performance computing support from Yellowstone (ark:/85065/d7wd3xhc) provided by NCAR's Computational and Information Systems Laboratory, sponsored by the National Science Foundation. We thank the AMPERE team and the AMPERE Science Center for providing the Iridium derived data products. All model output, simulation codes, and analysis routines are being preserved on the NCAR High-Performance Storage System and will be made available upon written request to the lead author of this publication. (NNX14AI13G - NASA; NNX13AF92G - NASA; NNX16AB80G - NASA; National Science Foundation; ACI-1053575 - National Science Foundation

Propagation of gamma rays and production of free electrons in air

A new concept of remote detection of concealed radioactive materials has been recently proposed \cite{Gr.Nusin.2010}-\cite{NusinSprangle}. It is based on the breakdown in air at the focal point of a high-power beam of electromagnetic waves produced by a THz gyrotron. To initiate the avalanche breakdown, seed free electrons should be present in this focal region during the electromagnetic pulse. This paper is devoted to the analysis of production of free electrons by gamma rays leaking from radioactive materials. Within a hundred meters from the radiation source, the fluctuating free electrons appear with the rate that may exceed significantly the natural background ionization rate. During the gyrotron pulse of about 10 microsecond length, such electrons may seed the electric breakdown and create sufficiently dense plasma at the focal region to be detected as an unambiguous effect of the concealed radioactive material.Comment: 27 pages, 10 figure

A fibered description of the vector-valued spectrum

For Banach spaces X and Y we study the vector-valued spectrum (Formula presented.), that is the set of non null algebra homomorphisms from (Formula presented.) to (Formula presented.), which is naturally projected onto the closed unit ball of (Formula presented.). The aim of this article is to describe the fibers defined by this projection, searching for analytic balls and considering Gleason parts.Fil: Dimant, Veronica Isabel. Universidad de San Andrés. Departamento de Matemáticas y Ciencias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Singer, Joaquín Camilo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Matemática; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigaciones Matemáticas "Luis A. Santaló". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Matemáticas "Luis A. Santaló"; Argentin

The mediating effect of task presentation on collaboration and children's acquisition of scientific reasoning

There has been considerable research concerning peer interaction and the acquisition of children's scientific reasoning. This study investigated differences in collaborative activity between pairs of children working around a computer with pairs of children working with physical apparatus and related any differences to the development of children's scientific reasoning. Children aged between 9 and 10 years old (48 boys and 48 girls) were placed into either same ability or mixed ability pairs according to their individual, pre-test performance on a scientific reasoning task. These pairs then worked on either a computer version or a physical version of Inhelder and Piaget's (1958) chemical combination task. Type of presentation was found to mediate the nature and type of collaborative activity. The mixed-ability pairs working around the computer talked proportionally more about the task and management of the task; had proportionally more transactive discussions and used the record more productively than children working with the physical apparatus. Type of presentation was also found to mediated children's learning. Children in same ability pairs who worked with the physical apparatus improved significantly more than same ability pairs who worked around the computer. These findings were partially predicted from a socio-cultural theory and show the importance of tools for mediating collaborative activity and collaborative learning

Direct detection of alpha synuclein oligomers in vivo

Background: Rat models of Parkinson’s disease are widely used to elucidate the mechanisms underlying disease etiology or to investigate therapeutic approaches. Models were developed using toxins such as MPTP or 6-OHDA to specifically target dopaminergic neurons resulting in acute neuronal loss in the substantia nigra or by using viral vectors to induce the specific and gradual expression of alpha synuclein in the substantia nigra. The detection of alpha- synuclein oligomers, the presumed toxic species, in these models and others has been possible using only indirect biochemical approaches to date. Here we coinjected AAVs encoding alpha-synuclein fused to the N- or C-terminal half of VenusYFP in rat substantia nigra pars compacta and describe for the first time a novel viral vector rodent model with the unique ability to directly detect and track alpha synuclein oligomers ex vivo and in vivo. Results: Viral coinjection resulted in widespread VenusYFP signal within the nigrostriatal pathway, including cell bodies in the substantia nigra and synaptic accumulation in striatal terminals, suggestive of in vivo alpha-synuclein oligomers formation. Transduced rats showed alpha-synuclein induced dopaminergic neuron loss in the substantia nigra, the appearance of dystrophic neurites, and gliosis in the striatum. Moreover, we have applied in vivo imaging techniques in the living mouse to directly image alpha-synuclein oligomers in the cortex. Conclusion: We have developed a unique animal model that provides a tool for the Parkinson’s disease research community with which to directly detect alpha- synuclein oligomers in vivo and screen therapeutic approaches targeting alpha-synuclein oligomers

Nurses’ perceptions of the root causes of community‐acquired pressure ulcers: Application of the Model for Examining Safety and Quality Concerns in Home Healthcare

Abstract Aims and objectives To explore how the context of care influences the development of community‐acquired pressure ulcers from the perspective of nurses working in home healthcare settings, to identify and categorise the factors perceived as contributing to the development of these ulcers using the Model for Examining Safety and Quality Concerns in Home Healthcare, and to explore how these risks are managed in practice. Background Pressure ulcer reduction is a priority in both hospital and community settings. Evidence suggests the factors affecting safety and performance in community settings are not the same as in hospital. However, research pertaining to pressure ulcer risk management has predominantly been undertaken in hospital settings. Design The study was framed by a qualitative exploratory design. Methods Semistructured interviews were conducted with a purposive sample of 19 registered nurses recruited from an independent regional tissue viability network and five community nursing provider organisations in London. Results The experiences and perceptions of participants mapped onto the components of the Model for Examining Safety and Quality Concerns in Home HealthCare: patient characteristics, provider characteristics, nature of home healthcare tasks, social and community environment, medical devices and new technology, physical environment, and external environment. Four strategies to address identified risks were established: behavioural interventions, technical interventions, safeguarding interventions and initiatives to promote better integration between health, local authorities and families. Conclusion Understanding the complex interplay between people and other elements of the healthcare system is critical to the prevention, management and investigation of pressure ulcers. This study has illuminated these elements from the perspective of nurses working in community settings. Relevance to clinical practice Further consideration should be given to the importance of place when both developing risk management strategies for pressure ulcer prevention and learning the lessons from failure

Comparison of predictive estimates of high‐latitude electrodynamics with observations of global‐scale Birkeland currents

Two of the geomagnetic storms for the Space Weather Prediction Center Geospace Environment Modeling challenge occurred after data were first acquired by the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE). We compare Birkeland currents from AMPERE with predictions from four models for the 4–5 April 2010 and 5–6 August 2011 storms. The four models are the Weimer (2005b) field‐aligned current statistical model, the Lyon‐Fedder‐Mobarry magnetohydrodynamic (MHD) simulation, the Open Global Geospace Circulation Model MHD simulation, and the Space Weather Modeling Framework MHD simulation. The MHD simulations were run as described in Pulkkinen et al. (2013) and the results obtained from the Community Coordinated Modeling Center. The total radial Birkeland current, ITotal, and the distribution of radial current density, Jr, for all models are compared with AMPERE results. While the total currents are well correlated, the quantitative agreement varies considerably. The Jr distributions reveal discrepancies between the models and observations related to the latitude distribution, morphologies, and lack of nightside current systems in the models. The results motivate enhancing the simulations first by increasing the simulation resolution and then by examining the relative merits of implementing more sophisticated ionospheric conductance models, including ionospheric outflows or other omitted physical processes. Some aspects of the system, including substorm timing and location, may remain challenging to simulate, implying a continuing need for real‐time specification.Key PointsPresents the first comparison between observed field‐aligned currents and models previously evaluated for space weather operational useThe model and observed integrated currents are well correlated, but the ratio between them ranges from 1/3 to 3The 2‐D current densities are weakly correlated with observations implying significant areas for improvements in the modelsPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136469/1/swe20415_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136469/2/swe20415.pd

Modeling Ionospheric Absorption Modified by Anomalous Heating During Substorms

Abstract. Riometers monitor the changes in ionospheric conductivity by measuring the absorption of very high frequency radio noise of galactic origin passing through the ionosphere. In this Letter the absorption of radio signals by a thin layer of ionospheric plasma, produced by ionization due to energetic precipitating electrons, is modeled by taking into account strong turbulent heating caused by instabilities. The precipitating electron population is obtained from a global MHD simulation of the magnetosphere, along with the electric fields which excite the Farley-Buneman instability and lead to turbulent electron heating. A comparison, the first of its kind, of the data from polar and sub-auroral riometers for the magnetic cloud event of January 10, 1997 shows good agreement. The ionospheric conductance modified by turbulent electron heating can be used to improve the magnetosphereionosphere coupling in the current global MHD models