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We report on prolonged enhancements of electron fluxes at energies at or above 500 keV, observed in the magnetotail by the lunar‐orbiting Acceleration, Reconnection, Turbulence, and Electrodynamics of Moon's Interaction with the Sun (ARTEMIS) during the recovery phase of a magnetic storm with minimum Dst${D}_{st}$≈${\\approx} $−200 nT during periodic auroral electrojet (AE$AE$ ) activations. The enhanced energetic electron fluxes were omnidirectional and observed near the magnetic equator. No solar energetic particle background was detected. Although ARTEMIS detected earthward magnetic flux transport impulses exceeding 2 mV/m, along with associated broadband electrostatic fluctuations, no correlation was evident between these phenomena and the relativistic electron flux enhancements. Spectra obtained during the relativistic electron flux enhancements are fit by the Kappa function, κ$\\kappa $= 3.75, similar to that of the quiet‐time plasma sheet electron population at lunar distance. Multiple reconnection events at large distances are, most likely, responsible for the electron heating.

Earth's magnetotail contains magnetic energy derived from the kinetic energy of the solar wind. Conversion of that energy back to particle energy ultimately powers Earth's auroras, heats the magnetospheric plasma, and energizes the Van Allen radiation belts. Where and how such electromagnetic energy conversion occurs has been unclear. Using a conjunction between eight spacecraft, we show that this conversion takes place within fronts of recently reconnected magnetic flux, predominantly at 1-to 10-electron inertial length scale, intense electrical current sheets (tens to hundreds of nanoamperes per square meter). Launched continually during intervals of geomagnetic activity, these reconnection outflow flux fronts convert ~10 to 100 gigawatts per square Earth radius of power, consistent with local magnetic flux transport, and a few times 10¹⁵ joules of magnetic energy, consistent with global magnetotail flux reduction.

Motivated by recent observations of intense electric fields and elevated energetic particle fluxes within flow bursts beyond geosynchronous altitude (Runov et al., 2009, 2011), we apply modeling of particle guiding centers in prescribed but realistic electric fields to improve our understanding of energetic particle acceleration and transport toward the inner magnetosphere through model‐data comparisons. Representing the vortical nature of an earthward traveling flow burst, a localized, westward‐directed transient electric field flanked on either side by eastward fields related to tailward flow is superimposed on a nominal steady state electric field. We simulate particle spectra observed at multiple THEMIS spacecraft located throughout the magnetotail and fit the modeled spectra to observations, thus constraining properties of the electric field model. We find that a simple potential electric field model is capable of explaining the presence and spectral properties of both geosynchronous altitude and “trans‐geosynchronous” injections at higher L‐shells (L > 6.6 RE) in a manner self‐consistent with the injections' inward penetration. In particular, despite the neglect of the magnetic field changes imparted by dipolarization and the inductive electric field associated with them, such a model can adequately describe the physics of both dispersed injections and depletions (“dips”) in energy flux in terms of convective fields associated with earthward flow channels and their return flow. The transient (impulsive), localized, and vortical nature of the earthward‐propagating electric field pulse is what makes this model particularly effective. Key Points We adapted a numerical model of particle GC motion in prescribed electric fields We simulate (trans‐)geosynchronous injection features: eflux enhancements & dips We explain e‐ acceleration & transport by impulsive, localized electric E‐fields

We discuss results of a superposed epoch analysis of dipolarization fronts, rapid (δt < 30 s), high‐amplitude (δBz > 10 nT) increases in the northward magnetic field component, observed during six Time History of Events and Macroscale Interactions during Substorms (THEMIS) conjunction events. All six fronts propagated earthward; time delays at multiple probes were used to determine their propagation velocity. We define typical magnetic and electric field and plasma parameter variations during dipolarization front crossings and estimate their characteristic gradient scales. The study reveals (1) a rapid 50% decrease in plasma density and ion pressure, (2) a factor of 2–3 increase in high‐energy (30–200 keV) electron flux and electron temperature, and (3) transient enhancements of ∼5 mV/m in duskward and earthward electric field components. Gradient scales of magnetic field, plasma density, and particle flux were found to be comparable to the ion thermal gyroradius. Current densities associated with the Bz increase are, on average, 20 nA/m2, 5–7 times larger than the current density in the cross‐tail current sheet. Because j · E > 0, the dipolarization fronts are kinetic‐scale dissipative regions with Joule heating rates of 10% of the total bursty bulk flow energy. Key Points Superposed epoch analysis of THEMIS dipolarization front events Common pattern in field and particle variations during front crossings Particle energization and energetic plasma transport

We report THEMIS observations of a dipolarization front, a sharp, large‐amplitude increase in the Z‐component of the magnetic field. The front was detected in the central plasma sheet sequentially at X = −20.1 RE (THEMIS P1 probe), at X = −16.7 RE (P2), and at X = −11.0 RE (P3/P4 pair), suggesting its earthward propagation as a coherent structure over a distance more than 10 RE at a velocity of 300 km/s. The front thickness was found to be as small as the ion inertial length. Comparison with simulations allows us to interpret the front as the leading edge of a plasma fast flow formed by a burst of magnetic reconnection in the midtail.

Observations of three closely‐spaced THEMIS spacecraft at 9–11 Re near midnight and close to the neutral sheet are used to investigate a sharp injection/dipolarization front (SDF) propagating inward in the flow‐braking region. This SDF was a very thin current sheet along the North‐South direction embedded within an Earthward‐propagating flow burst. A short‐lived depression of the total magnetic field (down to 1 nT), devoid of wave activity and intense particle fluxes, stays ahead of the SDF. Clear finite proton gyroradius effects, which help visualize the geometry and sub‐gyroscale of the SDF, are seen centered at the thin current sheet. The SDF nearly coincides with the narrow interface between plasmas of different densities and temperatures. At that interface, we observed strong (40–60 mV/m peak) E‐field bursts of the lower‐hybrid time scale that are confined to a localized region of density depletions. This sharp dipolarization/injection front propagating in the flow‐braking region appears to be a complicated kinetic‐scale plasma structure that combines a number of small‐scale elements (Bz drops, thin current sheets, LH cavities, injection fronts) previously discussed as separate objects.

We present multipoint observations of magnetotail plasma sheet dynamics during an event in which magnetic reconnection and dipolarization were observed at −16 < X < −15 RE (mid‐tail) and at −10 < X < −4.8 RE (near‐Earth plasma sheet), respectively. Timing analysis of the observations shows that the near‐Earth dipolarization was a consequence of mid‐tail reconnection. Large‐amplitude magnetic field oscillations were observed in the temporal and spatial vicinity of the reconnection site. Interpreted as current sheet flapping, they enable reconstruction of a complex sheet structure with an embedded thin current sheet of ion inertial scale size. Detailed analysis of the orientation of the dipolarization front and of plasma motions around it reveals that the front of the reconnection jet was interchange unstable. Key Points Signatures of reconnection were observed in the midmagnetotail Earthward moving dipolarization front was observed in the near plasma sheet Evidence for front formation due to reconnection is presented

We report on the evolving ion distributions associated with the arrival of an earthward propagating dipolarization front in the near‐Earth magnetotail using Time History of Events and Macroscale Interactions during Substorms (THEMIS). Ion distributions exhibit steady duskward anisotropy well before the front arrival, suggesting thin current sheet formation at ∼11 RE, during the growth phase of a moderate geomagnetic substorm. As the dipolarization front moves closer, an additional, earthward streaming ion population appears, resulting in an earthward velocity moment. This population eventually overwhelms the preexisting duskward anisotropy and merges with the earthward convecting bulk flow once the dipolarization front arrives. Test‐particle simulations show that the observed ion evolution is consistent with a picture of ions reflected and accelerated by the approaching front and moving ahead of it.

Human papillomaviruses of high carcinogenic risk (HR HPVs) are major etiological agents of malignant diseases of the cervix, vulva, penis, anal canal, larynx, head, and neck. Prophylactic vaccination against HPV, which mainly covers girls and women under 25, does not prevent vertical and horizontal HPV transmission in infants and children and does not have a therapeutic effect. As a result, a significant proportion of the population is not protected from the HPV infection and development of HPV-associated neoplastic transformation and cancer, which indicates the need for development and intro- duction of therapeutic HPV vaccines. Unlike prophylactic vaccines aimed at the formation of virus-neutralizing antibodies, therapeutic vaccines elicit cellular immune response leading to the elimination of infected and malignant cells expressing viral proteins. The ideal targets for vaccine immunotherapy are highly conserved HR HPV oncoproteins E6 and E7 expressed in precancerous and tumor tissues. Here, we describe expression of these proteins during different stages of HPV infection, their antigenic and immunogenic properties, and T-cell epitopes, the response to which correlates with natural regression of HPV-induced neoplastic changes. The review describes patterns of E6 and E7 oncoproteins presentation to the immune system as components of candidate vaccines along with the results of the most promising preclinical trials and animal models used in these trials. Special attention is paid to vaccine candidates which have shown efficacy in clinical trials in patients with HPV-associated neoplastic changes.

Dawn–dusk asymmetries are ubiquitous features of the coupled solar-wind–magnetosphere–ionosphere system. During the last decades, increasing availability of satellite and ground-based measurements has made it possible to study these phenomena in more detail. Numerous publications have documented the existence of persistent asymmetries in processes, properties and topology of plasma structures in various regions of geospace. In this paper, we present a review of our present knowledge of some of the most pronounced dawn–dusk asymmetries. We focus on four key aspects: (1) the role of external influences such as the solar wind and its interaction with the Earth's magnetosphere; (2) properties of the magnetosphere itself; (3) the role of the ionosphere and (4) feedback and coupling between regions. We have also identified potential inconsistencies and gaps in our understanding of dawn–dusk asymmetries in the Earth's magnetosphere and ionosphere.