scholarly journals Magnetosphere dynamics during the 14 November 2012 storm inferred from TWINS, AMPERE, Van Allen Probes, and BATS-R-US–CRCM

2018 ◽  
Vol 36 (1) ◽  
pp. 107-124 ◽  
Author(s):  
Natalia Buzulukova ◽  
Jerry Goldstein ◽  
Mei-Ching Fok ◽  
Alex Glocer ◽  
Phil Valek ◽  
...  
Keyword(s):  
Large Scale ◽  
System Level ◽  
Global Changes ◽  
Magnetospheric Substorms ◽  
Tail Region ◽  
Particle Injection ◽  
Magnetospheric Configuration And Dynamics ◽  
Van Allen Probes ◽  
Low Altitude ◽  
Birkeland Currents

Abstract. During the 14 November 2012 geomagnetic storm, the Van Allen Probes spacecraft observed a number of sharp decreases (“dropouts”) in particle fluxes for ions and electrons of different energies. In this paper, we investigate the global magnetosphere dynamics and magnetosphere–ionosphere (M–I) coupling during the dropout events using multipoint measurements by Van Allen Probes, TWINS, and AMPERE together with the output of the two-way coupled global BATS-R-US–CRCM model. We find different behavior for two pairs of dropouts. For one pair, the same pattern was repeated: (1) weak nightside Region 1 and 2 Birkeland currents before and during the dropout; (2) intensification of Region 2 currents after the dropout; and (3) a particle injection detected by TWINS after the dropout. The model predicted similar behavior of Birkeland currents. TWINS low-altitude emissions demonstrated high variability during these intervals, indicating high geomagnetic activity in the near-Earth tail region. For the second pair of dropouts, the structure of both Birkeland currents and ENA emissions was relatively stable. The model also showed quasi-stationary behavior of Birkeland currents and simulated ENA emissions with gradual ring current buildup. We confirm that the first pair of dropouts was caused by large-scale motions of the OCB (open–closed boundary) during substorm activity. We show the new result that this OCB motion was associated with global changes in Birkeland (M–I coupling) currents and strong modulation of low-altitude ion precipitation. The second pair of dropouts is the result of smaller OCB disturbances not related to magnetospheric substorms. The local observations of the first pair of dropouts result from a global magnetospheric reconfiguration, which is manifested by ion injections and enhanced ion precipitation detected by TWINS and changes in the structure of Birkeland currents detected by AMPERE. This study demonstrates that multipoint measurements along with the global model results enable the reconstruction of a more complete system-level picture of the dropout events and provides insight into M–I coupling aspects that have not previously been investigated. Keywords. Magnetospheric physics (magnetosphere–ionosphere interactions; magnetospheric configuration and dynamics); space plasma physics (numerical simulation studies)

scholarly journals Proton isotropy boundaries as measured on mid- and low-altitude satellites

2005 ◽  
Vol 23 (5) ◽  
pp. 1839-1847 ◽  
Author(s):  
N. Yu. Ganushkina ◽  
T. I. Pulkkinen ◽  
M. V. Kubyshkina ◽  
V. A. Sergeev ◽  
E. A. Lvova ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Current Sheet ◽  
Pitch Angle ◽  
Large Field ◽  
Tail Region ◽  
Isotropic Distribution ◽  
Distribution Boundary ◽  
Magnetospheric Configuration And Dynamics ◽  
Low Altitude ◽  
The Difference

Abstract. Polar CAMMICE MICS proton pitch angle distributions with energies of 31-80 keV were analyzed to determine the locations where anisotropic pitch angle distributions (perpendicular flux dominating) change to isotropic distributions. We compared the positions of these mid-altitude isotropic distribution boundaries (IDB) for different activity conditions with low-altitude isotropic boundaries (IB) observed by NOAA 12. Although the obtained statistical properties of IDBs were quite similar to those of IBs, a small difference in latitudes, most pronounced on the nightside and dayside, was found. We selected several events during which simultaneous observations in the same local time sector were available from Polar at mid-altitudes, and NOAA or DMSP at low-altitudes. Magnetic field mapping using the Tsyganenko T01 model with the observed solar wind input parameters showed that the low- and mid-altitude isotropization boundaries were closely located, which leads us to suggest that the Polar IDB and low-altitude IBs are related. Furthermore, we introduced a procedure to control the difference between the observed and model magnetic field to reduce the large scatter in the mapping. We showed that the isotropic distribution boundary (IDB) lies in the region where Rc/ρ~6, that is at the boundary of the region where the non-adiabatic pitch angle scattering is strong enough. We therefore conclude that the scattering in the large field line curvature regions in the nightside current sheet is the main mechanism producing isotropization for the main portion of proton population in the tail current sheet. This mechanism controls the observed positions of both IB and IDB boundaries. Thus, this tail region can be probed, in its turn, with observations of these isotropy boundaries. Keywords. Magnetospheric physics (Energetic particles, Precipitating; Magnetospheric configuration and dynamics; Magnetotail)

Building a Culture of Ethical, Comparable, Authentic Assessment

2019 ◽  
pp. 463-481
Author(s):  
Andrew Reid ◽  
Julie Ballantyne
Keyword(s):  
Teaching And Learning ◽  
Large Scale ◽  
Authentic Assessment ◽  
Subject Area ◽  
Music Educators ◽  
System Level ◽  
Diverse Range ◽  
Effective Learning ◽  
School Based ◽  
The Subject

In an ideal world, assessment should be synonymous with effective learning and reflect the intricacies of the subject area. It should also be aligned with the ideals of education: to provide equitable opportunities for all students to achieve and to allow both appropriate differentiation for varied contexts and students and comparability across various contexts and students. This challenge is made more difficult in circumstances in which the contexts are highly heterogeneous, for example in the state of Queensland, Australia. Assessment in music challenges schooling systems in unique ways because teaching and learning in music are often naturally differentiated and diverse, yet assessment often calls for standardization. While each student and teacher has individual, evolving musical pathways in life, the syllabus and the system require consistency and uniformity. The challenge, then, is to provide diverse, equitable, and quality opportunities for all children to learn and achieve to the best of their abilities. This chapter discusses the designing and implementation of large-scale curriculum as experienced in secondary schools in Queensland, Australia. The experiences detailed explore the possibilities offered through externally moderated school-based assessment. Also discussed is the centrality of system-level clarity of purpose, principles and processes, and the provision of supportive networks and mechanisms to foster autonomy for a diverse range of music educators and contexts. Implications for education systems that desire diversity, equity, and quality are discussed, and the conclusion provokes further conceptualization and action on behalf of students, teachers, and the subject area of music.

scholarly journals Drug Prescription Profiles in Patients with Polypharmacy in Spain: A Large-Scale Pharmacoepidemiologic Study Using Real-World Data

2021 ◽  
Vol 18 (9) ◽  
pp. 4754
Author(s):  
Miguel Ángel Hernández-Rodríguez ◽  
Ermengol Sempere-Verdú ◽  
Caterina Vicens-Caldentey ◽  
Francisca González-Rubio ◽  
Félix Miguel-García ◽  
...  
Keyword(s):  
Psychotropic Drugs ◽  
Large Scale ◽  
Anatomical Therapeutic Chemical ◽  
Drug Prescription ◽  
Age Groups ◽  
System Level ◽  
Real World Data ◽  
Converting Enzyme Inhibitors ◽  
Cross Sectional ◽  
Β Blockers

We aimed to identify and compare medication profiles in populations with polypharmacy between 2005 and 2015. We conducted a cross-sectional study using information from the Computerized Database for Pharmacoepidemiologic Studies in Primary Care (BIFAP, Spain). We estimated the prevalence of therapeutic subgroups in all individuals 15 years of age and older with polypharmacy (≥5 drugs during ≥6 months) using the Anatomical Therapeutic Chemical classification system level 4, by sex and age group, for both calendar years. The most prescribed drugs were proton-pump inhibitors (PPIs), statins, antiplatelet agents, benzodiazepine derivatives, and angiotensin-converting enzyme inhibitors. The greatest increases between 2005 and 2015 were observed in PPIs, statins, other antidepressants, and β-blockers, while the prevalence of antiepileptics was almost tripled. We observed increases in psychotropic drugs in women and cardiovascular medications in men. By patient´s age groups, there were notable increases in antipsychotics, antidepressants, and antiepileptics (15–44 years); antidepressants, PPIs, and selective β-blockers (45–64 years); selective β-blockers, biguanides, PPIs, and statins (65–79 years); and in statins, selective β-blockers, and PPIs (80 years and older). Our results revealed important increases in the use of specific therapeutic subgroups, like PPIs, statins, and psychotropic drugs, highlighting opportunities to design and implement strategies to analyze such prescriptions’ appropriateness.

scholarly journals Integration of enzyme constraints in a genome-scale metabolic model of Aspergillus niger improves phenotype predictions

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Jingru Zhou ◽  
Yingping Zhuang ◽  
Jianye Xia
Keyword(s):  
Aspergillus Niger ◽  
Large Scale ◽  
Measurement Techniques ◽  
Metabolic Model ◽  
System Level ◽  
Metabolic Phenotype ◽  
Omics Data ◽  
Prediction Ability ◽  
Phenotype Prediction ◽  
Genome Scale

Abstract Background Genome-scale metabolic model (GSMM) is a powerful tool for the study of cellular metabolic characteristics. With the development of multi-omics measurement techniques in recent years, new methods that integrating multi-omics data into the GSMM show promising effects on the predicted results. It does not only improve the accuracy of phenotype prediction but also enhances the reliability of the model for simulating complex biochemical phenomena, which can promote theoretical breakthroughs for specific gene target identification or better understanding the cell metabolism on the system level. Results Based on the basic GSMM model iHL1210 of Aspergillus niger, we integrated large-scale enzyme kinetics and proteomics data to establish a GSMM based on enzyme constraints, termed a GEM with Enzymatic Constraints using Kinetic and Omics data (GECKO). The results show that enzyme constraints effectively improve the model’s phenotype prediction ability, and extended the model’s potential to guide target gene identification through predicting metabolic phenotype changes of A. niger by simulating gene knockout. In addition, enzyme constraints significantly reduced the solution space of the model, i.e., flux variability over 40.10% metabolic reactions were significantly reduced. The new model showed also versatility in other aspects, like estimating large-scale $$k_{{cat}}$$ k cat values, predicting the differential expression of enzymes under different growth conditions. Conclusions This study shows that incorporating enzymes’ abundance information into GSMM is very effective for improving model performance with A. niger. Enzyme-constrained model can be used as a powerful tool for predicting the metabolic phenotype of A. niger by incorporating proteome data. In the foreseeable future, with the fast development of measurement techniques, and more precise and rich proteomics quantitative data being obtained for A. niger, the enzyme-constrained GSMM model will show greater application space on the system level.

scholarly journals 3D Photon-To-Digital Converter for Radiation Instrumentation: Motivation and Future Works

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 598
Author(s):  
Jean-François Pratte ◽  
Frédéric Nolet ◽  
Samuel Parent ◽  
Frédéric Vachon ◽  
Nicolas Roy ◽  
...  
Keyword(s):  
Large Scale ◽  
Single Photon ◽  
Time Of Flight ◽  
Digital Signal ◽  
Liquid Argon ◽  
Cmos Technology ◽  
System Level ◽  
Superior Performance ◽  
Digital Converter ◽  
Positron Emission

Analog and digital SiPMs have revolutionized the field of radiation instrumentation by replacing both avalanche photodiodes and photomultiplier tubes in many applications. However, multiple applications require greater performance than the current SiPMs are capable of, for example timing resolution for time-of-flight positron emission tomography and time-of-flight computed tomography, and mitigation of the large output capacitance of SiPM array for large-scale time projection chambers for liquid argon and liquid xenon experiments. In this contribution, the case will be made that 3D photon-to-digital converters, also known as 3D digital SiPMs, have a potentially superior performance over analog and 2D digital SiPMs. A review of 3D photon-to-digital converters is presented along with various applications where they can make a difference, such as time-of-flight medical imaging systems and low-background experiments in noble liquids. Finally, a review of the key design choices that must be made to obtain an optimized 3D photon-to-digital converter for radiation instrumentation, more specifically the single-photon avalanche diode array, the CMOS technology, the quenching circuit, the time-to-digital converter, the digital signal processing and the system level integration, are discussed in detail.

Barriers and levers for implementing sustainable Nature-Based Solutions in cities

2021 ◽  
Author(s):  
Chloé Duffaut ◽  
Nathalie Frascaria-Lacoste ◽  
Pierre-Antoine Versini
Keyword(s):  
Urban Areas ◽  
Large Scale ◽  
Project Managers ◽  
Global Changes ◽  
Human Beings ◽  
Urban Context ◽  
Urban Plan ◽  
Education And Awareness ◽  
Awareness Raising ◽  
The City

<p>Hydro-meteorological risks are increasing and this could be due to global changes. These risks are particularly important in the urban context where most human beings live. Indeed, the impervious surfaces present in cities increase the risk of flooding, for example. Nature-Based Solutions can help to reduce these risks by creating permeable soils or storing water while promoting biodiversity. In this context, it is essential to understand what hinders the development and sustainability of these Nature-based Solutions in the city and what could help to deploy them on a large scale. For this purpose, various professionals working on Nature-Based Solutions in the city in France, were interviewed between 2020 and 2021, both in the academic and operational sectors, or even at the interface between the two: researchers in ecology or hydrology, IUCN (International Union for Conservation of Nature) project manager, project managers at the Regional Biodiversity Agency, director and natural environment manager of a watershed union, agro-economists engineer among others. They were asked what are the barriers and potential opportunities for Nature-Based Solutions implementation and sustainability in city. By analysing their answers, it emerges that the obstacles are more often cultural, political or financial than technical. The potential levers often mentioned are education and awareness-raising at all levels, especially for elected officials and the general public. Regulations such as the PLU (Local Urban Plan) and new funding for more natural spaces in the city also seem to be means of promoting Nature-based Solutions in urban areas. These interviews with diverse professionals directly involved in Nature-Based Solutions in cities allow to give real courses of action to be taken to democratize these Solutions throughout the French territory, or even internationally, and therefore ultimately reduce the risks of hydro-meteorology. This is one of the objectives of the French ANR project EVNATURB (Assessment of ecosystem performance of a renaturation of the urban environment), in which this study has been carried out.</p>

Implementing post-trial access plans for HIV prevention research

2018 ◽  
Vol 44 (5) ◽  
pp. 354-358 ◽  
Author(s):  
Amy Paul ◽  
Maria W Merritt ◽  
Jeremy Sugarman
Keyword(s):  
Hiv Prevention ◽  
Large Scale ◽  
Healthcare Systems ◽  
System Level ◽  
Planning Under Uncertainty ◽  
Work Related ◽  
Prevention Trials ◽  
Practical Experiences ◽  
Post Trial ◽  
Local Healthcare

Ethics guidance increasingly recognises that researchers and sponsors have obligations to consider provisions for post-trial access (PTA) to interventions that are found to be beneficial in research. Yet, there is little information regarding whether and how such plans can actually be implemented. Understanding practical experiences of developing and implementing these plans is critical to both optimising their implementation and informing conceptual work related to PTA. This viewpoint is informed by experiences with developing and implementing PTA plans for six large-scale multicentre HIV prevention trials supported by the HIV Prevention Trials Network. These experiences suggest that planning and implementing PTA often involve challenges of planning under uncertainty and confronting practical barriers to accessing healthcare systems. Even in relatively favourable circumstances where a tested intervention medication is approved and available in the local healthcare system, system-level barriers can threaten the viability of PTA plans. The aggregate experience across these HIV prevention trials suggests that simply referring participants to local healthcare systems for PTA will not necessarily result in continued access to beneficial interventions for trial participants. Serious commitments to PTA will require additional efforts to learn from future approaches, measuring the success of PTA plans with dedicated follow-up and further developing normative guidance to help research stakeholders navigate the complex practical challenges of realising PTA.

scholarly journals Implementation of the Omega (ω) Index to detect large-scale systematic cheating

2019 ◽  
Author(s):  
Alvin Vista
Keyword(s):  
Standardized Testing ◽  
Large Scale ◽  
Type I Error ◽  
R Package ◽  
Statistical Testing ◽  
System Level ◽  
Control Group ◽  
Type I ◽  
Data Contamination ◽  
Cheating Detection

Cheating detection is an important issue in standardized testing, especially in large-scale settings. Statistical approaches are often computationally intensive and require specialised software to conduct. We present a two-stage approach that quickly filters suspected groups using statistical testing on an IRT-based answer-copying index. We also present an approach to mitigate data contamination and improve the performance of the index. The computation of the index was implemented through a modified version of an open source R package, thus enabling wider access to the method. Using data from PIRLS 2011 (N=64,232) we conduct a simulation to demonstrate our approach. Type I error was well-controlled and no control group was falsely flagged for cheating, while 16 (combined n=12,569) of the 18 (combined n=14,149) simulated groups were detected. Implications for system-level cheating detection and further improvements of the approach were discussed.

scholarly journals RESEARCH ON THE KEY TECHNOLOGY OF LARGE SCALE MAPPING FROM LOW ALTITUDE PHOTOGRAMMETRY

2016 ◽  
Vol XLI-B1 ◽  
pp. 789-796
Author(s):  
Wu Bo-Yi ◽  
Zhang Ning ◽  
Su Guo-Zhong
Keyword(s):  
Large Scale ◽  
Shanxi Province ◽  
Successful Implementation ◽  
Control Points ◽  
Theoretic Analysis ◽  
Ground Control Points ◽  
Traditional Procedure ◽  
Map Processing ◽  
Low Altitude ◽  
Wide Angle Camera

Based on the theoretic analysis of the accuracy in large scale photogrammetric mapping, some defects in traditional procedure were discussed. A set of key technologies dedicate to accuracy improvement in low altitude photogrammetry were analyzed in detail, namely the utilization of wide angle camera and low altitude flight, enhancement in image matching, predesigned layout of Ground Control Points (GCPs) in field survey, optimization of adjustment model and improvement in map processing. Besides, a low altitude aerial unmanned airship system was established. Finally, successful implementation in 1:500 topographic mapping project in built-up areas of 30 counties in Shanxi Province proves the practicability and effectiveness of the proposed approaches.

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