Auroral Research Articles

Development of a 23-color flow cytometry panel for the characterization of myelomonocytic differentiation with applications for MRD testing.

Abstract It is well agreed that measurable residual disease (MRD) testing in acute leukemia patients following induction chemotherapy has profound prognostic implications. Flow cytometry is well suited to be the mainstay for MRD testing due to the heterogenous immunophenotypic and molecular natures of leukemia. Current flow cytometry MRD testing involves examination of more than 15 antigens, requiring multiple tubes to be run for each patient as current clinical flow cytometers are limited to examining 12 parameters per tube. Because multiple tubes are required, hematopathologists must infer antigen expression between tubes, which can be difficult. As MRD testing has such prognostic implications and defines treatment stratifications and outcomes, MRD testing requires very high sensitivity. While several groups have improved sensitivity by increasing the number of cells analyzed, we propose that increasing the antigenic targets in a single immunophenotyping assay will improve sensitivity by enhancing our ability to differentiate normal from abnormal hematopoietic cells. To test this, we utilized spectral flow cytometry, which allows for targeting more parameters with the same number of lasers for a single instrument. We developed a 23-color flow cytometry panel which was designed to thoroughly examine myelomonocytic differentiation and included multiple other antigenic targets which are known to be aberrantly expressed on leukemia cells. The panel also included a live-dead stain to exclude dead cells from analysis. All data was collected with a 3-laser Cytek Northern Lights spectral flow cytometer, which can analyze 10 million events in ~10 minutes. We tested this panel on more than 50 bone marrow aspirate samples, including normal samples, multiple myeloid leukemias, myelodysplastic samples, as well as more than 20 aspirate samples which also had MRD testing completed at a reference laboratory. Our results for MRD testing had excellent concordance with results from the gold-standard reference laboratory method. As our method only required one tube to be run per sample, we were routinely able to analyze at least 10 million cells per sample. Using in silico modelling from our data, we determined the sensitivity of our assay to be an average of 0.005% (range 0.002 – 0.015%) depending on the specific immunophenotype, when analyzing 10 million cells. As we examined all marker expression in a single tube, we were able to model sensitivity as if only 10-parameters were collected per tube and inference was required between tubes for analysis as is the current standard practice. We found that our 23-color assay was significantly more sensitive (p =0.02) compared to running multiple 10-color tubes and inferring between samples. Overall, higher parameter flow cytometric assays (>20 markers) allow for a more sensitive and robust MRD analysis than current gold-standard methods and should be explored for utilization in the clinical setting.

From physics of polar aurora to changes of the fundamental approaches to the physics of the magnetospheric processes

One of the main problems of modern magnetospheric physics is the lack of a self-consistent explanation of the main physical processes based on the laws of plasma physics. Among all the traditionally studied phenomena, the polar aurora stands out for being key to our understanding of several magnetospheric processes. In this manuscript, I would like to share with the younger generation my view about main auroral processes which I have developed during my career over the past 50 years.

Triplet state harvesting and search for forbidden transition intensity in the nitrogen molecule.

Triplet excited states of the N2 molecule play an important role in electric discharges through air or liquid nitrogen accompanied by various afterglows. In the rarefied upper atmosphere, they produce aurora borealis and participate in other energy-transfer processes connected with atmospheric photochemistry and nightglow. In this work, we present spin-orbit coupling calculations of the intensity of various forbidden transitions, including the prediction of the electric dipole transition moment of the new band, which is strongly prohibited by the (+|-) selection rule, the new spin-induced magnetic transition, magnetic and electric quadrupole transitions for the B3Πg Wilkinson band, and the Lyman-Birge-Hopfield a1Πg ← X1Σg transition. Also, two other far-UV singlet-singlet quadrupole transitions are calculated for the first time, namely, the Dressler-Lutz a"1Σg +-X1Σg + and the less studied z1Δg-X1Σg + weak transitions.

On the green isolated proton auroras during Canada thanksgiving geomagnetic storm

The existence of detached/isolated auroral structures in the subauroral ionosphere has been recognized and studied for decades. One major subset of such detached auroras is the so-called “isolated proton aurora” (IPA). IPA is characterized by substantial hydrogen emissions and thus inferred to be proton aurora, but is also accompanied by other emission lines. In particular, IPA is usually dominated by 557.7 nm green-line emissions in optical luminosity. To date, there is still a lack of dedicated spectrographic study and detailed comparison among structures in different emission lines of IPA. The intensity ratios between the 557.7 nm and hydrogen emissions in IPA have not been well established from concurrent observations or theoretical models. In this study, we report an IPA event during ∼0245–0345 UT on 12 October 2021, the Canada Thanksgiving storm night. Using multi-station, multi-wavelength optical instruments, including the Transition Region Explorer (TREx) spectrograph, we investigate the evolution and spectrographic properties of the IPA. In-situ and ground magnetometer data show evidence of electromagnetic ion cyclotron (EMIC) waves associated with the passage of IPA, supporting a causal link between the EMIC wave and the proton precipitation. The precipitating proton energies are estimated to range between a few keV and a few tens of keV according to the IPA emission heights inferred from triangulation analyses. Via careful examination of the spectral intensities and the elevation-angle profiles of the 557.7, 427.8, and 486.1 nm emissions based on the spectrograph data, we conclude that the 557.7 nm emissions contained in the IPA were unlikely to owe their source to energetic electron precipitation from the magnetosphere, but were the byproduct of the proton precipitation. The intensity ratio between the 557.7 nm (427.8 nm) and the 486.1 nm emissions of the IPA are confined within a relatively narrow range around ∼26 (∼4), which may serve as validation tests for existing and developing proton transport models.

Localized mesospheric ozone destruction corresponding to isolated proton aurora coming from Earth’s radiation belt

Relativistic electron precipitation (REP) from the Earth’s radiation belt plays an important role in mesospheric ozone loss as a connection between space weather and the climate system. However, the rapid (tens of minutes) destruction of mesospheric ozone directly caused by REP has remained poorly understood due to the difficulty of recognizing its location and duration. Here we show a compelling rapid correspondence between localized REP and ozone destruction during a specific auroral phenomenon, the called an isolated proton aurora (IPA). The IPA from the Earth’s radiation belt becomes an important spatial and temporal proxy of REP, distinct from other auroral phenomena, and allowing visualizing micro-ozone holes. We found ozone destruction of as much as 10–60% within 1.5 h of the initiation of IPA. Electromagnetic ion cyclotron waves in the oxygen ion band observed as the driver of REP likely affect through resonance with mainly ultra-relativistic (> 2 mega-electron-volts) energy electrons. The rapid REP impact demonstrates its crucial role and direct effect on regulating the atmospheric chemical balance.

A screening assessment of the impact of sedimentological heterogeneity on CO2 migration and stratigraphic-baffling potential: Johansen and Cook formations, Northern Lights project, offshore Norway

• Johansen-Cook storage unit consists predominantly of wave-dominated deltaic sandstones. • Novel method used to screen impact of sedimentological heterogeneity on CO 2 migration and stratigraphic-baffling potential. • Screening method combines experimental design, sketch-based reservoir modelling and single-phase flow diagnostics. • Multiple types of sedimentological heterogeneity have significant effects. We use a method combining experimental design, sketch-based reservoir modelling, and single-phase flow diagnostics to rapidly screen the impact of sedimentological heterogeneities that constitute baffles and barriers to CO 2 migration in the Johansen and Cook formations at the Northern Lights CO 2 storage site. The types and spatial organisation of sedimentological heterogeneities in the wave-dominated deltaic sandstones of the Johansen-Cook storage unit are constrained using core data from the 31/5-7 (Eos) well, previous interpretations of seismic data and regional well-log correlations, and outcrop and subsurface analogues. Delta planform geometry, clinoform dip, and facies-association interfingering extent along clinoforms control: (1) the distribution and connectivity of high-permeability medial and proximal delta-front sandstones, (2) effective horizontal and vertical permeability characteristics of the storage unit, and (3) pore volumes injected at breakthrough time (which approximates the efficiency of stratigraphic baffling). In addition, the lateral continuity of carbonate-cemented concretionary layers along transgressive surfaces impacts effective vertical permeability, and bioturbation intensity impacts effective horizontal and vertical permeability. The combined effects of these and other heterogeneities are also influential. Our results suggest that the baffling effect on CO 2 migration and retention of sedimentological heterogeneity is an important precursor for later capillary, dissolution and mineral trapping.

Convulsed States: Earthquakes, Prophecy, and the Remaking of Early America by Jonathan Todd Hancock

Reviewed by: Convulsed States: Earthquakes, Prophecy, and the Remaking of Early America by Jonathan Todd Hancock Adam Jortner Convulsed States: Earthquakes, Prophecy, and the Remaking of Early America. By Jonathan Todd Hancock. Chapel Hill: University of North Carolina Press, 2021. 208 pages. Cloth, paper, ebook. By any measure, 1811 was a bad year. It had itinerant prophets predicting doom, comets in the sky, a theater fire, a November war in the Old Northwest, and the shattering New Madrid earthquakes in December that tossed the Mississippi River around the Missouri bootheel. No wonder one nineteenth-century commentator called it an “Annus Mirabilis” (12)—year of miracles. But 1811 has yet to receive the microscopic examination of other critical years; in popular and political histories, 1776, 1861, and 1968 still crowd out 1811. Jonathan Todd Hancock aims to change that with Convulsed States, a monograph that centers the quakes among associated contemporary disasters as a way of generating “a continental, cross-cultural perspective on prophecy and revivalism, state formations, and understandings of environmental change across Native American, African American, and Euro American societies” (3). How did the quakes, once drafted into religion, politics, and culture, he asks, change the peoples of the Americas? Did this bad year shift America from a Jeffersonian to a Jacksonian persuasion? And how did literally unstable land affect a metaphorically unstable U.S. land policy? Hancock tackles these big questions in a series of thematic chapters, beginning with an exploration of how different communities experienced the earthquakes and concluding with an examination of how the federal response to the quakes both initiated a flood of land speculation and shaped Indian policy. Hancock does not dwell on the many dramatic contemporary accounts of the earthquakes themselves. As the book points out, some of the most popular stories about the quakes were likely “fable and burlesque” (15); contemporaries (and historians) recognized that U.S. newspapers at the time did not diligently pursue accuracy but reprinted whatever they could get their hands on.1 The oft-repeated claim that the New Madrid quakes caused church bells to ring in Boston, Hancock notes, probably derives from a misreading of “Charlestown” (Massachusetts) for “Charleston” (South Carolina). As for the Mississippi River running backwards? It could have happened, Hancock notes, but only in certain places, not along the whole river. [End Page 662] The quakes unquestionably did desolate New Madrid, however, prompting a variety of governmental responses. In 1815, for the first time, Congress appropriated relief funds for Americans. These took the form of free public lands, which in turn initiated “decades of speculation, fraud, and legal wrangling” (111) that ultimately forced the Quapaw nation off their land in Arkansas. Hancock also points to the federal government’s conflicts with the region’s Native American prophets, some of whom, he suggests—especially the Red Stick prophets—drafted the earthquake into their preaching. Moreover, the Red Sticks’ defeat in 1814 led directly to Andrew Jackson’s mass appropriation of Creek land in Alabama. The fear and uncertainty provoked by the quakes, Hancock argues, resulted in the seizure of Indigenous land. In between describing the quakes and the land policy that followed them, Convulsed States takes readers through contemporary earthquake explanations and associated phenomena—the wonders that made 1811 the Annus Mirabilis. The perspectives on such phenomena articulated in the political and religious preaching of Native American prophets receive much attention. Along with the rise of the Red Sticks in Creek territory, Hancock devotes most of his attention to the Shawnee Prophet, Tenskwatawa, who received credit for predicting the earthquake, while noting that other Native American prophets may have adopted ideas about earthquakes as divine punishment. Christian evangelists also sought to make hay from the earthquakes. Convulsed States focuses on Nimrod Hughes and others who declared that the End Was Nigh, words that may have gained added urgency in the wake of New Madrid. From there, Hancock launches into a condensed overview of religious responses to a host of other troubles in the Annus Mirabilis—northern lights, comets, local intrigues, and rumors of war with Britain. The book allots a good amount of space to these religious upheavals, but it never quite identifies what (if...

Impact of the COVID-19 pandemic on human-nature relations in a remote nature-based tourism destination.

Tourism and nature-based recreation has changed dramatically during the COVID-19 pandemic. Travel restrictions caused sharp declines in visitation numbers, particularly in remote areas, such as northern Norway. In addition, the pandemic may have altered human-nature relationships by changing visitor behaviour and preferences. We studied visitor numbers and behaviour in northern Norway, based on user-generated data, in the form of photographic material that was uploaded to the popular online platform Flickr. A total of 195.200 photographs, taken by 5.247 photographers were subjected to Google's "Cloud Vision" automatic content analysis algorithm. The resulting collection of labels that were assigned to each photograph was analysed in structural topic models, using photography date (relative to the start of the pandemic measures in Norway) and reported or estimated photographers' nationality as explanatory variables. Our results show that nature-based recreation relating to "mountains" and "winter" became more prevalent during the pandemic, amongst both domestic and international photographers. Shifts in preferences due to the pandemic outbreak strongly depended on nationality, with domestic visitors demonstrating a wide interest in topics while international visitors maintained their preference for nature-based experiences. Among those activities that suffered the most from decline in international tourism was northern lights and cruises as indicated by the topic models. On the other hand, images depicting mountains and flora and fauna increased their prevalence during the pandemic. Domestic visitors, on the other hand, spent more time in urban settings as a result of restrictions, which results in a higher prevalence of non-nature related images. Our results underscore the need to consider the dynamic nature of human-nature relationships. The contrast in flexibility to adapt to changing conditions and travel restrictions should be incorporated in collaborative efforts of municipalities and tour operators to develop sustainable local nature-based tourism products, particularly in remote areas.

My dealings with the aurora borealis

Two important decisions on my career path had the consequence that, after a quarter century of experimentation with barium plasma clouds, I was directing my research more and more towards physics of the auroral borealis. The combination of ground-based optical and radar observations and two national satellite missions were our means to deepen the understanding of the plasma physics background of the aurora, especially of discrete auroral arcs. Our contributions are put in perspective with the global research in this field by a quick run through the major steps in the exploration of the physics of the aurora. Although by the end of the 20th century all key ingredients for the understanding of auroral arcs were available, the present state leaves many open questions, foremost with respect to the true generators processes and the overall flow of momentum and energy. Some of these questions I tried to address during my retirement years.

The influence of various pesticide loads on the development of late blight and potato alternariоsis in the Central region of Russia

Field experiments were conducted to test three schemes for the use of drugs of different action spectra in order to reduce the chemical load on the potato biocenosis. The experiments were carried out on four varieties differing in resistance to late blight. According to the results of two-year tests, it was revealed that on resistant varieties Grand, Kumach and medium-resistant varieties Gulliver, even in epiphytotic years for late blight, it is possible to use alternating preparations, which reduces the chemical load by 33.3%. On the Northern Lights variety unstable to late blight, only a chemical scheme can be used in such years. In the years with the depressive development of late blight, the use of any schemes was not very effective. Etching of planting tubers with Edikum preparation in some years reduces the germination of Grand and Gulliver varieties by 90-70%, Kumach and Northern Lights varieties by 13-16%, which negatively affects potato yields.

MapAI: Precision in Building Segmentation

MapAI: Precision in Building Segmentation is a competition arranged with the Norwegian Artificial Intelligence Research Consortium (NORA) in collaboration with Centre for Artificial Intelligence Research at the University of Agder (CAIR), the Norwegian Mapping Authority, AI:Hub, Norkart, and the Danish Agency for Data Supply and Infrastructure. The competition will be held in the fall of 2022. It will be concluded at the Northern Lights Deep Learning conference focusing on the segmentation of buildings using aerial images and laser data. We propose two different tasks to segment buildings, where the first task can only utilize aerial images, while the second must use laser data (LiDAR) with or without aerial images. Furthermore, we use IoU and Boundary IoU to properly evaluate the precision of the models, with the latter being an IoU measure that evaluates the results' boundaries. We provide the participants with a training dataset and keep a test dataset for evaluation.

Formula omitted] cooling in the jovian aurora: Juno remote sensing observations and modeling

Cooling of Jupiter's auroral thermosphere by H3+ radiation to space is one of the processes controlling the energy balance in the auroral upper atmosphere. The UltraViolet Spectrograph (UVS) and the Jupiter InfraRed Auroral Mapper (JIRAM) on board Juno have observed the Jovian polar aurora from its polar orbit since August 2016. The UVS instrument measures the H2 Lyman and Werner bands whose brightness is a proxy of the precipitated auroral electron flux. The 3.3–3.6 μm spectral window of the JIRAM L-band imager maps the H3+ thermal radiance with unprecedented spatial resolution. Comparison of concurrent observations indicates that the morphological features are similar in the two spectral regions but differences are also observed in the spatial intensity contrast. We compare the total (direct and indirect) particle heating rate and the cooling by H3+ radiation derived from four pairs of simultaneous UVS and JIRAM images. The total auroral cooling power H3+ is in the range 2–4 terawatts in both hemispheres. In all cases, the H3+ cooling in the aurora is found to range between 0.45 and 0.67 time less than the particle collisional heating. In a second step, we use the ultraviolet H2 brightness and FUV color ratio to derive the characteristics of the electron precipitation and model the H3+ radiance for each UVS map pixel. The comparison of the H3+ modeled radiance map with the JIRAM observations shows general good agreement with some local differences. The four spatially integrated H3+ cooling power from the model are in very good agreement with the JIRAM values. These results are important constraints for global magnetosphere-ionosphere-atmosphere models.

Becoming Ordinary: The Aurora Borealis during the Reformation

Becoming Ordinary: The Aurora Borealis during the Reformation

Multi‐Event Study of Simultaneous Observations of Isolated Proton Auroras at Subauroral Latitudes Using Ground All‐Sky Imagers and the Van Allen Probes

AbstractIsolated proton auroras (IPAs) appearing at subauroral latitudes are generated by energetic protons precipitating from the magnetosphere through interaction with electromagnetic ion cyclotron (EMIC) waves. Thus, an IPA is the ionospheric projection of the spatial and temporal variation of wave‐particle interaction regions in the magnetosphere. In this study, we conducted unique multi‐event analysis of simultaneous observations of IPAs and their source regions on 22 April, 7 September, and 22 March 2018, using all‐sky imagers at subauroral latitudes and the Van Allen Probes. When the satellite footprint passed over the IPAs associated with ground Pc1 geomagnetic pulsations, locally generated He+‐band EMIC waves with the same frequencies as the ground Pc1 pulsations were observed in all events. The IPAs and EMIC waves had comparable narrow widths in the latitudinal direction. The EMIC waves appeared during the rapid enhancement of the ring current proton flux at energy range of ∼10–50 keV, while they disappeared at the rapid decrease of the electron density. From these results, we conclude that the boundaries of the localized IPAs and EMIC waves were determined by the overlap region of energetic proton enhancement and the plasmasphere. This overlap of ring‐current protons and plasmasphere is a favorable condition for the pitch‐angle scattering of protons by the EMIC waves. Characteristic magnetic and electric field variations with the IPAs were not observed by the satellite, indicating that the IPAs were not accompanied by field‐aligned currents comparable to that of oval auroral arcs.

Patchy Proton Aurora at Mars: A Global View of Solar Wind Precipitation Across the Martian Dayside From EMM/EMUS

AbstractProton aurora at Mars are thought to form indirectly, as a result of solar wind proton charge exchange with planetary coronal hydrogen upstream of the bow shock. This charge exchange produces beamed energetic neutral atoms that bypass the induced magnetosphere and cause spatially uniform auroral emission when they collide with the thermosphere. Here we report multiple definitive observations of spatially localized “patchy” proton aurora at Mars using the Emirates Mars Ultraviolet Spectrometer on the Emirates Mars Mission, and characterize the plasma environment during these events using contemporaneous Mars Atmosphere and Volatile EvolutioN mission measurements. Multiple mechanisms are required to explain these observations, including at times the direct deposition of solar wind plasma into the thermosphere, particularly during radial interplanetary magnetic field conditions. Much future work will be needed to assess these mechanisms and understand the impact of these auroral events on Mars atmospheric evolution.

Corona Discharges on von Reichenbach’s Terrellae?

In the 1840s, extensive experimentation led von Reichenbach to postulate an ‘Odic force’ associated with ‘Odic light’ or ‘magnet light’, of which the polar aurora would be an example in space. The physical nature of the visible phenomena reported by his assistants during the experiments has never been satisfactorily identified. It is argued that ‘Od’ compares to plasma or ionised gas, while at least a subset of the investigations, conducted on terrellae, represented the first experimental work on corona discharges. Accordingly, the glows on the terrellae cannot be directly compared to the aurora.

Proton aurora and relativistic electron microbursts scattered by electromagnetic ion cyclotron waves

Charged particle precipitation from Earth’s magnetosphere results in stunning displays of the aurora and energy transfer into the atmosphere. Some of this precipitation is caused by wave-particle interactions. In this study, we present an example of a wave-particle interaction between Electromagnetic Ion Cyclotron waves, and magnetospheric protons and electrons. This interaction resulted in a co-located isolated proton aurora and relativistic electron microbursts. While isolated proton aurora is widely believed to be caused by Electromagnetic Ion Cyclotron waves, this unique observation suggests that these waves can also scatter relativistic electron microbursts. Theoretically, nonlinear interactions between Electromagnetic Ion Cyclotron waves and electrons are necessary to produce the intense sub-second microburst precipitation. Lastly, detailed analysis of the auroral emissions suggests that no chorus waves were present during the event. This is in contrast to the most commonly associated driver of microbursts, whistler mode chorus waves, and supports other less commonly considered driving mechanisms.

Introduction

The thirteenth volume in the series presents all articles on the aurora borealis that were published in the journal of the Swedish Societas Literaria / Societas Regia Literaria et Scientiarum (now Kungl. Vetenskaps-Societeten i Uppsala) from 1720 to 1729. The articles are by the adjunct/professor of astronomy in Uppsala, Erik Johan (Ericus Johannes) Burman; the professor of mathematics in Lund, Conrad (Conradus) Quensel; and the adjunct/professor of astronomy in Uppsala Anders (Andreas) Celsius. E. J. Burman developed a theory of two kinds of aurora borealis and inspired other investigators across Sweden to observe the phenomenon according to his instructions. The introduction, written by Latinist and historian of science Per Pippin Aspaas, consists of a short history of the society in the period including brief presentations of Burman, Quensel and Celsius. Furthermore, Aspaas summarizes the contents of all articles dealing with the aurora and presents extracts in English translation. First published in July 2022. In March 2023, an updated version with fulltext searchable facsimiles was published. Some insignificant typos were corrected and acknowledgements added to the Introduction.

Extracts from Acta Literaria Sveciae, Volumen Secundum (1725–1729)

The file is a facsimile of extracts from the second volume of the Acta Literaria Sveciae, covering all mentions of the aurora borealis in the journal from 1725 to 1729. For a detailed summary of contents, see the introduction by Per Pippin Aspaas. First published in July 2022. In March 2023, an updated facsimile with fulltext search functionality was published (see acknowledgements in the Introduction).

Extracts from Acta Literaria Sveciae, Volumen Primum (1720–1724)

The file is a facsimile of extracts from the first volume of the Acta Literaria Sveciae, covering all mentions of the aurora borealis in the journal from 1720 to 1724. For a detailed summary of contents, see the introduction by Per Pippin Aspaas. First published in July 2022. In March 2023, an updated facsimile with fulltext search functionality was published (see acknowledgements in the Introduction).