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1.	Bauer, M., et al. (author) Variations in seasonal solar insolation are associated with a history of suicide attempts in bipolar I disorder 2021 In: International Journal of Bipolar Disorders. - : Springer Science and Business Media LLC. - 2194-7511. ; 9:1 Journal article (peer-reviewed)abstract Background Bipolar disorder is associated with circadian disruption and a high risk of suicidal behavior. In a previous exploratory study of patients with bipolar I disorder, we found that a history of suicide attempts was associated with differences between winter and summer levels of solar insolation. The purpose of this study was to confirm this finding using international data from 42% more collection sites and 25% more countries. Methods Data analyzed were from 71 prior and new collection sites in 40 countries at a wide range of latitudes. The analysis included 4876 patients with bipolar I disorder, 45% more data than previously analyzed. Of the patients, 1496 (30.7%) had a history of suicide attempt. Solar insolation data, the amount of the sun's electromagnetic energy striking the surface of the earth, was obtained for each onset location (479 locations in 64 countries). Results This analysis confirmed the results of the exploratory study with the same best model and slightly better statistical significance. There was a significant inverse association between a history of suicide attempts and the ratio of mean winter insolation to mean summer insolation (mean winter insolation/mean summer insolation). This ratio is largest near the equator which has little change in solar insolation over the year, and smallest near the poles where the winter insolation is very small compared to the summer insolation. Other variables in the model associated with an increased risk of suicide attempts were a history of alcohol or substance abuse, female gender, and younger birth cohort. The winter/summer insolation ratio was also replaced with the ratio of minimum mean monthly insolation to the maximum mean monthly insolation to accommodate insolation patterns in the tropics, and nearly identical results were found. All estimated coefficients were significant at p < 0.01. Conclusion A large change in solar insolation, both between winter and summer and between the minimum and maximum monthly values, may increase the risk of suicide attempts in bipolar I disorder. With frequent circadian rhythm dysfunction and suicidal behavior in bipolar disorder, greater understanding of the optimal roles of daylight and electric lighting in circadian entrainment is needed.
2.	Bauer, M., et al. (author) Association between polarity of first episode and solar insolation in bipolar I disorder 2022 In: Journal of Psychosomatic Research. - : Elsevier BV. - 0022-3999 .- 1879-1360. ; 160 Journal article (peer-reviewed)abstract Objective: Circadian rhythm disruption is commonly observed in bipolar disorder (BD). Daylight is the most powerful signal to entrain the human circadian clock system. This exploratory study investigated if solar insolation at the onset location was associated with the polarity of the first episode of BD I. Solar insolation is the amount of electromagnetic energy from the Sun striking a surface area of the Earth. Methods: Data from 7488 patients with BD I were collected at 75 sites in 42 countries. The first episode occurred at 591 onset locations in 67 countries at a wide range of latitudes in both hemispheres. Solar insolation values were obtained for every onset location, and the ratio of the minimum mean monthly insolation to the maximum mean monthly insolation was calculated. This ratio is largest near the equator (with little change in solar insolation over the year), and smallest near the poles (where winter insolation is very small compared to summer insolation). This ratio also applies to tropical locations which may have a cloudy wet and clear dry season, rather than winter and summer. Results: The larger the change in solar insolation throughout the year (smaller the ratio between the minimum monthly and maximum monthly values), the greater the likelihood the first episode polarity was depression. Other associated variables were being female and increasing percentage of gross domestic product spent on country health expenditures. (All coefficients: P ≤ 0.001). Conclusion: Increased awareness and research into circadian dysfunction throughout the course of BD is warranted.
3.	Bauer, M., et al. (author) Exploratory study of ultraviolet B (UVB) radiation and age of onset of bipolar disorder 2023 In: International Journal of Bipolar Disorders. - 2194-7511. ; 11:1 Journal article (peer-reviewed)abstract BackgroundSunlight contains ultraviolet B (UVB) radiation that triggers the production of vitamin D by skin. Vitamin D has widespread effects on brain function in both developing and adult brains. However, many people live at latitudes (about > 40 N or S) that do not receive enough UVB in winter to produce vitamin D. This exploratory study investigated the association between the age of onset of bipolar I disorder and the threshold for UVB sufficient for vitamin D production in a large global sample.MethodsData for 6972 patients with bipolar I disorder were obtained at 75 collection sites in 41 countries in both hemispheres. The best model to assess the relation between the threshold for UVB sufficient for vitamin D production and age of onset included 1 or more months below the threshold, family history of mood disorders, and birth cohort. All coefficients estimated at P <= 0.001.ResultsThe 6972 patients had an onset in 582 locations in 70 countries, with a mean age of onset of 25.6 years. Of the onset locations, 34.0% had at least 1 month below the threshold for UVB sufficient for vitamin D production. The age of onset at locations with 1 or more months of less than or equal to the threshold for UVB was 1.66 years younger.ConclusionUVB and vitamin D may have an important influence on the development of bipolar disorder. Study limitations included a lack of data on patient vitamin D levels, lifestyles, or supplement use. More study of the impacts of UVB and vitamin D in bipolar disorder is needed to evaluate this supposition.
4.	Bauer, M., et al. (author) Solar insolation in springtime influences age of onset of bipolar I disorder 2017 In: Acta Psychiatrica Scandinavica. - : Wiley. - 0001-690X .- 1600-0447. ; 136:6, s. 571-582 Research review (peer-reviewed)abstract Objective: To confirm prior findings that the larger the maximum monthly increase in solar insolation in springtime, the younger the age of onset of bipolar disorder. Method: Data were collected from 5536 patients at 50 sites in 32 countries on six continents. Onset occurred at 456 locations in 57 countries. Variables included solar insolation, birth-cohort, family history, polarity of first episode and country physician density. Results: There was a significant, inverse association between the maximum monthly increase in solar insolation at the onset location, and the age of onset. This effect was reduced in those without a family history of mood disorders and with a first episode of mania rather than depression. The maximum monthly increase occurred in springtime. The youngest birth-cohort had the youngest age of onset. All prior relationships were confirmed using both the entire sample, and only the youngest birth-cohort (all estimated coefficients P < 0.001). Conclusion: A large increase in springtime solar insolation may impact the onset of bipolar disorder, especially with a family history of mood disorders. Recent societal changes that affect light exposure (LED lighting, mobile devices backlit with LEDs) may influence adaptability to a springtime circadian challenge.
5.	Wild, J. A., et al. (author) Midnight sector observations of auroral omega bands 2011 In: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 116, s. A00I30- Journal article (peer-reviewed)abstract We present observations of auroral omega bands on 28 September 2009. Although generally associated with the substorm recovery phase and typically observed in the morning sector, the features presented here occurred just after expansion phase onset and were observed in the midnight sector, dawnward of the onset region. An all-sky imager located in northeastern Iceland revealed that the omega bands were similar to 150 x 200 km in size and propagated eastward at similar to 0.4 km s(-1) while a colocated ground magnetometer recorded the simultaneous occurrence of Ps6 pulsations. Although somewhat smaller and slower moving than the majority of previously reported omega bands, the observed structures are clear examples of this phenomenon, albeit in an atypical location and unusually early in the substorm cycle. The THEMIS C probe provided detailed measurements of the upstream interplanetary environment, while the Cluster satellites were located in the tail plasma sheet conjugate to the ground-based all-sky imager. The Cluster satellites observed bursts of 0.1-3 keV electrons moving parallel to the magnetic field toward the Northern Hemisphere auroral ionosphere; these bursts were associated with increased levels of field-aligned Poynting flux. The in situ measurements are consistent with electron acceleration via shear Alfven waves in the plasma sheet similar to 8 R-E tailward of the Earth. Although a one-to-one association between auroral and magnetospheric features was not found, our observations suggest that Alfven waves in the plasma sheet are responsible for field-aligned currents that cause Ps6 pulsations and auroral brightening in the ionosphere. Our findings agree with the conclusions of earlier studies that auroral omega bands have a source mechanism in the midtail plasma sheet.
6.	Andersson, L., et al. (author) New Features of Electron Phase Space Holes Observed by the THEMIS Mission 2009 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 102:22, s. 225004- Journal article (peer-reviewed)abstract Observations of electron phase-space holes (EHs) in Earth's plasma sheet by the THEMIS satellites include the first detection of a magnetic perturbation (delta B-parallel to) parallel to the ambient magnetic field (B-0). EHs with a detectable delta B-parallel to have several distinguishing features including large electric field amplitudes, a magnetic perturbation perpendicular to B-0, high speeds (similar to 0.3c) along B-0, and sizes along B-0 of tens of Debye lengths. These EHs have a significant center potential (Phi similar to k(B)T(e)/e), suggesting strongly nonlinear behavior nearby such as double layers or magnetic reconnection.
7.	Bauer, Michael, et al. (author) Association between solar insolation and a history of suicide attempts in bipolar I disorder. 2019 In: Journal of psychiatric research. - : Elsevier BV. - 1879-1379 .- 0022-3956. ; 113, s. 1-9 Journal article (peer-reviewed)abstract In many international studies, rates of completed suicide and suicide attempts have a seasonal pattern that peaks in spring or summer. This exploratory study investigated the association between solar insolation and a history of suicide attempt in patients with bipolar I disorder. Solar insolation is the amount of electromagnetic energy from the Sun striking a surface area on Earth. Data were collected previously from 5536 patients with bipolar I disorder at 50 collection sites in 32 countries at a wide range of latitudes in both hemispheres. Suicide related data were available for 3365 patients from 310 onset locations in 51 countries. 1047 (31.1%) had a history of suicide attempt. There was a significant inverse association between a history of suicide attempt and the ratio of mean winter solar insolation/mean summer solar insolation. This ratio is smallest near the poles where the winter insolation is very small compared to the summer insolation. This ratio is largest near the equator where there is relatively little variation in the insolation over the year. Other variables in the model that were positively associated with suicide attempt were being female, a history of alcohol or substance abuse, and being in a younger birth cohort. Living in a country with a state-sponsored religion decreased the association. (All estimated coefficients p<0.01). In summary, living in locations with large changes in solar insolation between winter and summer may be associated with increased suicide attempts in patients with bipolar disorder. Further investigation of the impacts of solar insolation on the course of bipolar disorder is needed.
8.	Ergun, R. E., et al. (author) Observations of Double Layers in Earth's Plasma Sheet 2009 In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 102:15, s. 155002- Journal article (peer-reviewed)abstract We report the first direct observations of parallel electric fields (E-parallel to) carried by double layers (DLs) in the plasma sheet of Earth's magnetosphere. The DL observations, made by the THEMIS spacecraft, have E-parallel to signals that are analogous to those reported in the auroral region. DLs are observed during bursty bulk flow events, in the current sheet, and in plasma sheet boundary layer, all during periods of strong magnetic fluctuations. These observations imply that DLs are a universal process and that strongly nonlinear and kinetic behavior is intrinsic to Earth's plasma sheet.
9.	Eriksson, S., et al. (author) Magnetic island formation between large-scale flow vortices at an undulating postnoon magnetopause for northward interplanetary magnetic field 2009 In: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 114:2, s. A00C17- Journal article (peer-reviewed)abstract Time History of Events and Macroscale Interactions during Substorms multispacecraft observations are presented for a similar to 2-h-long postnoon magnetopause event on 8 June 2007 that for the first time indicate that the trailing (sunward) edges of Kelvin-Helmholtz (KH) waves are commonly related to small-scale < 0.56 R-E magnetic islands or flux transfer events (FTE) during the growth phase of these surface waves. The FTEs typically show a characteristic bipolar B-N structure with enhanced total pressure at their center. Most of the small-scale FTEs are not related to any major plasma acceleration. TH-A observations of one small FTE at a transition from the low-latitude boundary layer (LLBL) into a magnetosheath plasma depletion layer were reconstructed using separate techniques that together confirm the presence of a magnetic island within the LLBL adjacent to the magnetopause. The island was associated with a small plasma vortex and both features appeared between two large-scale (similar to 1 R-E long and 2000 km wide) plasma vortices. We propose that the observed magnetic islands may have been generated from a time-varying reconnection process in a low ion plasma beta (beta(i) < 0.2) and low 8.3 degrees field shear environment at the sunward edge of the growing KH waves where the local magnetopause current sheet may be compressed by the converging flow of the large-scale plasma vortices as suggested by numerical simulations of the KH instability.
10.	Johansson, T., et al. (author) Observation of an inner magnetosphere electric field associated with a BBF-like flow and PBIs 2009 In: Annales Geophysicae. - : Copernicus GmbH. - 0992-7689 .- 1432-0576. ; 27:4, s. 1489-1500 Journal article (peer-reviewed)abstract Themis E observed a perpendicular (to the magnetic field) electric field associated with an Earthward plasma flow at XGSM=-9.6 R-E on 11 January 2008. The electric field observation resembles Cluster observations closer to Earth in the auroral region. The fast plasma flow shared some characteristics with bursty bulk flows (BBFs) but did not meet the usual criteria in maximum velocity and duration to qualify as one. Themis C observed the same flow further downtail but Themis D, separated by only 1 R-E in azimuthal direction from Themis E, did not. At the time of the electric field and ion flow event, the all-sky imager and ground-based magnetometer at Rankin Inlet observed Poleward Boundary Intensifications (PBIs) and a negative bay signature. None of the other Themis ground-based observatories recorded any significant auroral or magnetic field activity, indicating that this was a localized activity. The joint Themis in situ and ground-based observations suggest that the two observations are related. This indicates that auroral electric fields can extend to regions much farther out than previously seen in Cluster observations.
11.	Oieroset, M., et al. (author) Reconnection With Magnetic Flux Pileup at the Interface of Converging ts at the Magnetopause 2019 In: Geophysical Research Letters. - : American Geophysical Union (AGU). - 0094-8276 .- 1944-8007. ; 46:4, s. 1937-1946 Journal article (peer-reviewed)abstract We report Magnetospheric Multiscale observations of reconnection in a in current sheet at the interface of interlinked flux tubes carried by nverging reconnection jets at Earth's magnetopause. The ion skin pth-scale width of the interface current sheet and the non-frozen-in ns indicate that Magnetospheric Multiscale crossed the reconnection yer near the X-line, through the ion diffusion region. Significant leup of the reconnecting component of the magnetic field in this and ree other events on approach to the interface current sheet was companied by an increase in magnetic shear and decrease in , leading conditions favorable for reconnection at the interface current sheet. e pileup also led to enhanced available magnetic energy per particle d strong electron heating. The observations shed light on the olution and energy release in 3-D systems with multiple reconnection tes. ain Language Summary The Earth and the solar wind magnetic fields terconnect through a process called magnetic reconnection. The newly connected magnetic field lines are strongly bent and accelerate rticles, similar to a rubber band in a slingshot. In this paper we ve used observations from NASA's Magnetospheric MultiScale spacecraft investigate what happens when two of these slingshot-like magnetic eld lines move toward each other and get tangled up. We found that the o bent magnetic field lines tend to orient themselves perpendicular to ch other as they become interlinked and stretched, similar to what bber bands would do. This reorientation allows the interlinked gnetic fields to reconnect again, releasing part of the built-up gnetic energy as strong electron heating. The results are important cause they show how interlinked magnetic fields, which occur in many lar and astrophysics contexts, reconnect and produce enhanced electron ating, something that was not understood before.
12.	Tao, J. B., et al. (author) A model of electromagnetic electron phase-space holes and its application 2011 In: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 116, s. A11213- Journal article (peer-reviewed)abstract Electron phase-space holes (EHs) are indicators of nonlinear activities in space plasmas. Most often they are observed as electrostatic signals, but recently Andersson et al. [2009] reported electromagnetic EHs observed by the THEMIS mission in the Earth's plasma sheet. As a follow-up to Andersson et al. [2009], this paper presents a model of electromagnetic EHs where the delta E x B(0) drift of electrons creates a net current. The model is examined with test-particle simulations and compared to the electromagnetic EHs reported by Andersson et al. [2009]. As an application of the model, we introduce a more accurate method than the simplified Lorentz transformation of Andersson et al. [2009] to derive EH velocity (v(EH)). The sizes and potentials of EHs are derived from v(EH), so an accurate derivation of v(EH) is important in analyzing EHs. In general, our results are qualitatively consistent with those of Andersson et al. [2009] but generally with smaller velocities and sizes.
13.	Tao, J. B., et al. (author) Kinetic instabilities in the lunar wake : ARTEMIS observations 2012 In: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 117, s. A03106- Journal article (peer-reviewed)abstract The Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) mission is a new two-probe lunar mission derived from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission. On 13 February 2010, one of the two probes, ARTEMIS P1 (formerly THEMIS-B), made the first lunar wake flyby of the mission. We present detailed analysis of the electrostatic waves observed on the outbound side of the flyby that were associated with electron beams. Halekas et al. (2011) derived a net potential across the lunar wake from observations and suggested that the net potential generated the observed electron beams and the electron beams in turn excited the observed electrostatic waves due to kinetic instabilities. The wavelengths and velocities of the electrostatic waves are estimated, using high-resolution electric field instrument data with cross-spectrum analysis and cross-correlation analysis. In general, the estimated wavelengths vary from a few hundred meters to a couple of thousand meters. The estimated phase velocities are on the order of 1000 km s(-1). In addition, we perform 1-D Vlasov simulations to help identify the mode of the observed electrostatic waves. We conclude that the observed electrostatic waves are likely on the electron beam mode branch.
14.	Angelopoulos, Angelos, et al. (author) Dispersion relation analysis of the neutral kaon regeneration amplitude in carbon 1999 In: European Physical Journal C. - : Springer Berlin/Heidelberg. - 1434-6044 .- 1434-6052. ; 10:1, s. 19-25 Journal article (peer-reviewed)abstract We apply a forward dispersion relation to the regeneration amplitude for kaon scattering on 12" style="position: relative;" tabindex="0" id="MathJax-Element-1-Frame" class="MathJax">12C using all available data. The CPLEAR data at low energies allow the determination of the net contribution from the subthreshold region which turns out to be much smaller than earlier evaluations, solving a long standing puzzle.
15.	Angelopoulos, A., et al. (author) K 0–KÌ„0 mass and decay-width differences : CPLEAR evaluation 1999 In: Physics Letters B. - : Elsevier. - 0370-2693 .- 1873-2445. ; 471:2, s. 332-338 Journal article (peer-reviewed)abstract The CPT-violation parameters Re(δ) and Im(δ) determined recently by CPLEAR are used to evaluate the K0– mass and decay-width differences, as given by the difference between the diagonal elements of the neutral-kaon mixing matrix (M−iΓ/2). The results – GeV and GeV – are consistent with CPT invariance. The CPT invariance is also shown to hold within a few times 10−3–10−4 for many of the amplitudes describing neutral-kaon decays to different final states.
16.	Angelopoulos, Angelos, et al. (author) K0â‡‹ KÌ„0 transitions monitored by strong interactions : a new determination of the K L–K S mass difference 2001 In: Physics Letters B. - : Elsevier. - 0370-2693 .- 1873-2445. ; 503:1, s. 49-57 Journal article (peer-reviewed)abstract The CPLEAR set-up (modified) has been used to determine the KL–KS mass difference by a method where neutral-kaon strangeness oscillations are monitored through kaon strong interactions, rather than semileptonic decays, thus requiring no assumptions on CPT invariance for the decay amplitudes. The result, Δm=(0.5343±0.0063stat±0.0025syst)×1010ℏ/s, provides a valuable input for CPT tests.
17.	Angelopoulos, Angelos, et al. (author) Physics at CPLEAR 2003 In: Physics Reports. - : Elsevier. ; 374:3, s. 165-270 Journal article (peer-reviewed)abstract LEAR offered unique opportunities to study the symmetries which exist between matter and antimatter. At variance with other approaches at this facility, CPLEAR was an experiment devoted to the study of CP, T and CPT symmetries in the neutral-kaon system. A variety of measurements allowed us to determine with high precision the parameters which describe the time evolution of the neutral kaons and their antiparticles, including decay amplitudes, and the related symmetry properties. Limits concerning quantum-mechanical predictions (EPR, coherence of the wave function) or the equivalence principle of general relativity have been obtained. An account of the main features of the experiment and its performances is given here, together with the results achieved.
18.	Angelopoulos, Konstantinos, et al. (author) Model predictive control for software systems with CobRA 2016 In: Proceedings - 11th International Symposium on Software Engineering for Adaptive and Self-Managing Systems, SEAMS 2016. - New York, NY, USA : ACM. - 9781450341875 ; , s. 35-46 Conference paper (peer-reviewed)abstract Self-adaptive software systems monitor their operation and adapt when their requirements fail due to unexpected phenomena in their environment. This paper examines the case where the environment changes dynamically over time and the chosen adaptation has to take into account such changes. In control theory, this type of adaptation is known as Model Predictive Control and comes with a well-developed theory and myriads of successful applications. The paper focuses on modelling the dynamic relationship between requirements and possible adaptations. It then proposes a controller that exploits this relationship to optimize the satisfaction of requirements relative to a cost-function. This is accomplished through a model-based framework for designing self-adaptive software systems that can guarantee a certain level of requirements satisfaction over time, by dynamically composing adaptation strategies when necessary. The proposed framework is illustrated and evaluated through a simulation of the Meeting-Scheduling System exemplar.
19.	Angelopoulos, M., et al. (author) Physical properties of sea ice cores from site BGC2 measured on legs 1 to 3 of the MOSAiC expedition 2022 In: PANGAEA. Other publication (other academic/artistic)abstract We present sea ice temperature and salinity data from first-year ice (FYI) and second-year ice (SYI) relevant to the temporal development of sea ice permeability and brine drainage efficiency from the early growth phase in October 2019 to the onset of spring warming in May 2020. Our dataset was collected in the central Arctic Ocean during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) Expedition in 2019 to 2020. MOSAiC was an international transpolar drift expedition in which the German icebreaker RV Polarstern anchored into an ice floe to gain new insights into Arctic climate over a full annual cycle. In October 2019, RV Polarstern moored to an ice floe in the Siberian sector of the Arctic at 85 degrees north and 137 degrees east to begin the drift towards the North Pole and the Fram Strait via the Transpolar Drift Stream. The data presented here were collected during the first three legs of the expedition, so all the coring activities took place on the same floe. The end dates of legs 1, 2, and 3 were 13 December, 24 February, and 4 June, respectively. The dataset contributed to a baseline study entitled, Deciphering the properties of different Arctic ice types during the growth phase of the MOSAiC floes: Implications for future studies. The study highlights downward directed gas pathways in FYI and SYI by inferring sea ice permeability and potential brine release from several time series of temperature and salinity measurements. The physical properties presented in this paper lay the foundation for subsequent analyses on actual gas contents measured in the ice cores, as well as air-ice and ice-ocean gas fluxes. Sea ice cores were collected with a Kovacs Mark II 9 cm diameter corer. To measure ice temperatures, about 4.5 cm deep holes were drilled into the core (intervals varied by site and leg) . The temperatures were measured by a digital thermometer within minutes after the cores were retrieved. The ice cores were placed into pre-labelled plastic sleeves sealed at the bottom end. The ice cores were transported to RV Polarstern and stored in a -20 degrees Celsius freezer. Each of the cores was sub-sampled, melted at room temperature, and processed for salinity within one or two days. The practical salinity was estimated by measuring the electrical conductivity and temperature of the melted samples using a WTW Cond 3151 salinometer equipped with a Tetra-Con 325 four-electrode conductivity cell. The practical salinity represents the the salinity estimated from the electrical conductivity of the solution. The dataset also contains derived variables, including sea ice density, brine volume fraction, and the Rayleigh number.
20.	Angelopoulos, V., et al. (author) First Results from the THEMIS Mission 2008 In: Space Science Reviews. - : Springer Science and Business Media LLC. - 0038-6308 .- 1572-9672. ; 141:1-4, s. 453-476 Research review (peer-reviewed)abstract THEMIS was launched on February 17, 2007 to determine the trigger and large-scale evolution of substorms. During the first seven months of the mission the five satellites coasted near their injection orbit to avoid differential precession in anticipation of orbit placement, which started in September 2007 and led to a commencement of the baseline mission in December 2007. During the coast phase the probes were put into a string-of-pearls configuration at 100 s of km to 2 R-E along-track separations, which provided a unique view of the magnetosphere and enabled an unprecedented dataset in anticipation of the first tail season. In this paper we describe the first THEMIS substorm observations, captured during instrument commissioning on March 23, 2007. THEMIS measured the rapid expansion of the plasma sheet at a speed that is commensurate with the simultaneous expansion of the auroras on the ground. These are the first unequivocal observations of the rapid westward expansion process in space and on the ground. Aided by the remote sensing technique at energetic particle boundaries and combined with ancillary measurements and MHD simulations, they allow determination and mapping of space currents. These measurements show the power of the THEMIS instrumentation in the tail and the radiation belts. We also present THEMIS Flux Transfer Events (FTE) observations at the magnetopause, which demonstrate the importance of multi-point observations there and the quality of the THEMIS instrumentation in that region of space.
21.	Artemyev, A. V., et al. (author) Field-Aligned Currents Originating From the Magnetic Reconnection Region : Conjugate MMS-ARTEMIS Observations 2018 In: Geophysical Research Letters. - : American Geophysical Union (AGU). - 0094-8276 .- 1944-8007. ; 45:12, s. 5836-5844 Journal article (peer-reviewed)abstract Near-Earth magnetic reconnection reconfigures the magnetotail and produces strong plasma flows that transport plasma sheet particles and electromagnetic energy to the inner magnetosphere. An essential element of such a reconfiguration is strong, transient field-aligned currents. These currents, believed to be generated within the plasma sheet and closed at the ionosphere, are responsible for magnetosphere-ionosphere coupling during substorms. We use conjugate measurements from Magnetospheric Multiscale (MMS) at the plasma sheet boundary (around x approximate to- 10R(E)) and Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) at the equator (around x approximate to- 60R(E)) to explore the potential generation region of these currents. We find a clear correlation between the field-aligned current intensity measured by MMS and the tailward plasma sheet flows measured by ARTEMIS. To better understand the origin of this correlation, we compare spacecraft observations with results from 3-D particle-in-cell simulations of magnetotail reconnection. The comparison reveals that field-aligned currents and plasma flows start, wax, and wane due to the development of a reconnection region between MMS (near-Earth) and ARTEMIS (at lunar distance). A weak correlation between the field-aligned current intensity at MMS and earthward flow magnitudes at ARTEMIS suggests that distant magnetotail reconnection does not significantly contribute to the generation of the observed near-Earth currents. Our findings support the idea that the dominant role of the near-Earth magnetotail reconnection in the field-aligned current generation is likely responsible for their transient nature, whereas more steady distant tail reconnection would support long-term field-aligned current system. Plain Language Summary Field-aligned currents connect the Earth magnetotail and ionosphere, proving energy and information transport from the region where main energy release process, magnetic reconnection, occurs to the region where the collisional energy dissipation takes place. Therefore, investigation and modeling of the field-aligned current generation is important problem of the magnetosphere plasma physics. However, field-aligned current investigation requires simultaneous observations of reconnection signatures in the magnetotail and at high latitudes. Simultaneous and conjugate operation of two multispacecraft missions, Magnetospheric Multiscale and Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun, for the first time provide an opportunity for such investigation. Combining spacecraft observations with results from 3-D particle-in-cell simulations of magnetotail reconnection, we demonstrate that field-aligned currents and plasma flows start, wax, and wane due to the development of a reconnection region between near-Earth (Magnetospheric Multiscale location) and lunar distant tail (Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon's Interaction with the Sun location). Our findings support the idea that the dominant role of the near-Earth magnetotail reconnection in the field-aligned current generation is likely responsible for their transient nature, whereas more steady distant tail reconnection would support long-term field-aligned current system.
22.	Dai, Lei, et al. (author) AME : A Cross-Scale Constellation of CubeSats to Explore Magnetic Reconnection in the Solar-Terrestrial Relation 2020 In: Frontiers in Physics. - : Frontiers Media SA. - 2296-424X. ; 8 Journal article (peer-reviewed)abstract A major subset of solar-terrestrial relations, responsible, in particular, for the driver of space weather phenomena, is the interaction between the Earth's magnetosphere and the solar wind. As one of the most important modes of the solar-wind-magnetosphere interaction, magnetic reconnection regulates the energy transport and energy release in the solar-terrestrial relation. In situ measurements in the near-Earth space are crucial for understanding magnetic reconnection. Past and existing spacecraft constellation missions mainly focus on the measurement of reconnection on plasma kinetic-scales. Resolving the macro-scale and cross-scale aspects of magnetic reconnection is necessary for accurate assessment and predictions of its role in the context of space weather. Here, we propose the AME (self-Adaptive Magnetic reconnection Explorer) mission consisting of a cross-scale constellation of 12+ CubeSats and one mother satellite. Each CubeSat is equipped with instruments to measure magnetic fields and thermal plasma particles. With multiple CubeSats, the AME constellation is intended to make simultaneous measurements at multiple scales, capable of exploring cross-scale plasma processes ranging from kinetic scale to macro scale.
23.	Fu, H. S., et al. (author) Whistler-mode waves inside flux pileup region : Structured or unstructured? 2014 In: Journal of Geophysical Research - Space Physics. - : Blackwell Publishing. - 2169-9380 .- 2169-9402. ; 119:11, s. 9089-9100 Journal article (peer-reviewed)abstract During reconnection, a flux pileup region (FPR) is formed behind a dipolarization front in an outflow jet. Inside the FPR, the magnetic field magnitude and Bz component increase and the whistler-mode waves are observed frequently. As the FPR convects toward the Earth during substorms, it is obstructed by the dipolar geomagnetic field to form a near-Earth FPR. Unlike the structureless emissions inside the tail FPR, we find that the whistler-mode waves inside the near-Earth FPR can exhibit a discrete structure similar to chorus. Both upper band and lower band chorus are observed, with the upper band having a larger propagation angle (and smaller wave amplitude) than the lower band. Most chorus elements we observed are rising-tone type, but some are falling-tone type. We notice that the rising-tone chorus can evolve into falling-tone chorus within <3s. One of the factors that may explain why the waves are unstructured inside the tail FPR but become discrete inside the near-Earth FPR is the spatial inhomogeneity of magnetic field: we find that such inhomogeneity is small inside the near-Earth FPR but large inside the tail FPR.
24.	Konstantinos, Angelopoulos, et al. (author) Engineering Self-Adaptive Software Systems : From Requirements to Model Predictive Control 2018 In: ACM Transactions on Autonomous and Adaptive Systems. - : Association for Computing Machinery (ACM). - 1556-4665 .- 1556-4703. ; 13:1 Journal article (peer-reviewed)abstract Self-adaptive software systems monitor their operation and adapt when their requirements fail due to unexpected phenomena in their environment. This article examines the case where the environment changes dynamically over time and the chosen adaptation has to take into account such changes. In control theory, this type of adaptation is known as Model Predictive Control and comes with a well-developed theory and myriad successful applications. The article focuses on modeling the dynamic relationship between requirements and possible adaptations. It then proposes a controller that exploits this relationship to optimize the satisfaction of requirements relative to a cost function. This is accomplished through a model-based framework for designing self-adaptive software systems that can guarantee a certain level of requirements satisfaction over time by dynamically composing adaptation strategies when necessary. The proposed framework is illustrated and evaluated through two simulated systems, namely, the Meeting-Scheduling exemplar and an E-Shop.
25.	Liang, J., et al. (author) Electromagnetic ELF wave intensification associated with fast earthward flows in mid-tail plasma sheet 2012 In: Annales Geophysicae. - : Copernicus GmbH. - 0992-7689 .- 1432-0576. ; 30:3, s. 467-488 Journal article (peer-reviewed)abstract In this study we perform a statistical survey of the extremely-low-frequency wave activities associated with fast earthward flows in the mid-tail central plasma sheet (CPS) based upon THEMIS measurements. We reveal clear trends of increasing wave intensity with flow enhancement over a broad frequency range, from below f(LH) (lower-hybrid resonant frequency) to above f(ce) (electron gyrofrequency). We mainly investigate two electromagnetic wave modes, the lower-hybrid waves at frequencies below f(LH), and the whistler-mode waves in the frequency range f(LH) < f < f(ce). The waves at f < f(LH) dramatically intensify during fast flow intervals, and tend to contain strong electromagnetic components in the high-plasma-beta CPS region, consistent with the theoretical expectation of the lower-hybrid drift instability in the center region of the tail current sheet. ULF waves with very large perpendicular wavenumber might be Doppler-shifted by the flows and also partly contribute to the observed waves in the lower-hybrid frequency range. The fast flow activity substantially increases the occurrence rate and peak magnitude of the electromagnetic waves in the frequency range f(LH) < f < f(ce), though they still tend to be short-lived and sporadic in occurrence. We also find that the electron pitch-angle distribution in the mid-tail CPS undergoes a variation from negative anisotropy (perpendicular temperature smaller than parallel temperature) during weak flow intervals, to more or less positive anisotropy (perpendicular temperature larger than parallel temperature) during fast flow intervals. The flow-related electromagnetic whistler-mode wave tends to occur in conjunction with positive electron anisotropy.

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