Abstract We present conjugate observations of ionospheric small‐scale magnetic perturbations (dB) and GPS scintillations from the Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS) and the Canadian High Arctic Ionospheric Network (CHAIN) during a storm‐time substorm on 9 August 2025 in the nightside auroral region. Rotational transverse dB of up to ∼1,000 nT, associated with filamentary field‐aligned currents (FACs) exceeding 150 μA/m2 on spatial scales of ∼1–16 km, were colocated with extreme, localized auroral scintillations (σϕ> 10 rad, S4≃ 0.3) and ∼10 dB‐Hz intensity reduction. The most intense scintillations lasted ∼1.5 s and coincided with peaks in auroral electrojets, Pi2 pulsations, and enhanced dTEC (∼12 TECU). The sheet‐like morphology and spatiotemporal correlation with auroral electrojets suggest that Farley–Buneman processes likely play a dominant role in scintillation formation, with additional contributions from FAC‐driven and gradient‐drift instabilities.

Space Weather Ionospheric Network Canada (SWINCan), formerly the Canadian High Arctic Ionospheric Network (CHAIN), has provided continuous, near-real-time monitoring of the high-latitude ionosphere since 2007. Capitalizing on Canada’s geographic expanse and proximity to the northern magnetic pole, SWINCan’s expansive instrument network delivers high-latitude ionospheric data including essential space environment quantities for scientific and operational use. This data enables fundamental understanding of the ionosphere and its role in radio propagation and solar-terrestrial interactions, while also providing critical input for ionosphere nowcast/forecast models that support scientific research and operations of navigation, communication, and radar systems at sub-auroral, auroral, and polar latitudes. In response to growing demand for enhanced high-latitude observational capacity, the Radio and Space Physics Laboratory (RSPL) at the University of New Brunswick is in the process of substantially expanding and modernizing SWINCan. By 2026, this pan-Canadian network will consist of 128 global navigation satellite system (GNSS) ionospheric scintillation and total electron content monitors (GISTMs) and 20 modernized high-frequency (HF) ionospheric sounders, adding to the 28 GISTMs and 10 HF sounders that are currently deployed. SWINCan GISTMs record raw 50 Hz/100 Hz data enabling study of the multi-spatiotemporal-scale structuring of the ionosphere, including fundamental study of radio wave scintillation in a turbulent ionosphere. As part of SWINCan modernization, RSPL has also developed a state-of-the-art, versatile HF platform to enhance SWINCan ionosonde systems. Updated systems are specifically designed for harsh environments such as the Arctic, are fully and remotely configurable, and are capable of interdependent experiments with other ground and spaceborne radio systems.

The ionosphere is a dynamic medium, that interacts with propagating radio waves through a variety of physical mechanisms. The characteristics and extent of the ionosphere's impact varies with season, local time, altitude, geographic and geomagnetic location, as well as helio-, geomagnetic, and terrestrial activity. On the other hand, the operation and reliability of many strategically important communication, navigation, and radar systems are subject to ionospheric conditions. A thorough understanding of physical mechanisms, accurate observation, as well as modeling of the state of the ionosphere are required. The combination of these facilitates the mitigation of detrimental influences on the operation of complex systems, or allow to utilize certain states of the ionosphere to an operational benefit, e.g. for long-range communication, through now- and forecasting of space weather.

We propose a rich foundational theory of typed data streams and stream transformers, motivated by two high-level goals. First, the type of a stream should be able to express complex sequential patterns of events over time. And second, it should describe the internal parallel structure of the stream, to support deterministic stream processing on parallel and distributed systems. To these ends, we introduce stream types , with operators capturing sequential composition, parallel composition, and iteration, plus a core calculus λ ST of transformers over typed streams that naturally supports a number of common streaming idioms, including punctuation, windowing, and parallel partitioning, as first-class constructions. λ ST exploits a Curry-Howard-like correspondence with an ordered variant of the Logic of Bunched Implication to program with streams compositionally and uses Brzozowski-style derivatives to enable an incremental, prefix-based operational semantics. To illustrate the programming style supported by the rich types of λ ST , we present a number of examples written in Delta, a prototype high-level language design based on λ ST .

The Global Positioning System (GPS) Attitude, Positioning, and Profiling (GAP) instrument is one of eight components of the scientific instrument suite onboard the Swarm-E satellite (previously CASSIOPE/e-POP). The Swarm-E instrument suite was designed to primarily study the physical processes coupling the polar ionosphere to the solar wind and magnetosphere. The GAP instrument consists of three GPS antennas oriented towards spacecraft zenith and one antenna oriented in the anti-ram direction, along with associated GPS receivers. This configuration allows for both radio occultation and topside ionosphere measurements, which are collected at data rates of up to 100 Hz. The elliptical, polar orbit of Swarm-E and high data rate of GAP allows for unique radio occultation and topside ionosphere observations, which is particularly useful for polar regions where much of the ionospheric structure and dynamic behaviour are not well observed or understood.

Motivated by distributed data processing applications, we introduce a class of labeled directed acyclic graphs constructed using sequential and parallel composition operations, and study automata and logics over them. We show that deterministic and non-deterministic acceptors over such graphs have the same expressive power, which can be equivalently characterized by Monadic Second-Order logic and the graded µ-calculus. We establish closure under composition operations and decision procedures for membership, emptiness, and inclusion. A key feature of our graphs, called synchronized series-parallel graphs (SSPG), is that parallel composition introduces a synchronization edge from the newly introduced source vertex to the sink. The transfer of information enabled by such edges is crucial to the determinization construction, which would not be possible for the traditional definition of series-parallel graphs. SSPGs allow both ordered ranked parallelism and unordered unranked parallelism. The latter feature means that in the corresponding automata, the transition function needs to account for an arbitrary number of predecessors by counting each type of state only up to a specified constant, thus leading to a notion of counting complexity that is distinct from the classical notion of state complexity. The determinization construction translates a nondeterministic automaton with n states and k counting complexity to a deterministic automaton with 2 n 2 states and kn counting complexity, and both these bounds are shown to be tight. Furthermore, for nondeterministic automata a bound of 2 on counting complexity suffices without loss of expressiveness.

Quantum entropy measures the number of possible microstates of position and momentum due to quantum uncertainty. Black hole entropy is an example of quantum entropy. Classical entropy, like the Gibbs entropy of a gas, does not depend on quantum uncertainty. This paper is the first to define the quantum entropy of ordinary matter, termed “atomic entropy”. The atomic entropy at the surface of a spherical object depends on its mass and is inversely proportional to its surface area. The entropy scale factor (ESF) is a theory that all changes in the scale of spacetime are due to differences in entropy. Defining atomic entropy allows the ESF to make predictions for systems including ordinary matter. In the ESF, gravitational objects are attracted to one another because gravitational entropy, a form of quantum entropy, increases as the distance between these objects decreases. The increase in gravitational entropy increases the total entropy of the system, in accordance with the second law of thermodynamics. This paper is also the first to use the gradients in the scale of space and time predicted by the ESF to derive Newtonian gravity. Explaining the mechanism of gravity in this way provides a link between quantum physics and gravity.

Gravitational redshift decreases the resolution of measurements, causing entropy by increasing the possible microstates of position and momentum for objects within a gravitational field. This is the first paper with a quantitative equation for gravitational entropy, which extends the concept of black hole entropy to any object within a gravitational field. It also provides the first calculation of “inertial entropy,” the entropy of moving objects, by correlating changes in the scale of spacetime due to gravity with those of special relativity. The entropy scale factor (ESF) combines gravitational entropy and inertial entropy to propose that all changes in the scale of spacetime are due to entropy. In the ESF, gravity is due to entropy, not the mass of Newtonian gravity or the energy and momentum of general relativity. The key difference between Newtonian gravity and the ESF is that mass is a property of an object, while gravitational entropy is a property of a field. This means that in the ESF the entropy of objects can be increased by the gravitational fields of nearby objects. This increase in entropy results in the ESF predicting more gravitational force than Newtonian gravity does for complicated systems. This increase in force may be able to explain the phenomena attributed to dark matter, like galaxy rotation dynamics, without the need for dark matter. The same changes in scale predicted by the ESF may be able to explain the expansion of the universe, both in the inflationary epoch and the accelerating universe, without the need for an inflaton field or dark energy. The similarity of the ESF to Newtonian gravity for systems with one or two gravitational bodies explains why it has not been ruled out by prior tests of gravity.

Purpose/Objective(s) In 2003, an article in the Harvard Business Review by Reichheld, et al, identified a simple single investigative question – "How likely is it that you would recommend [company X] to a friend or colleague?" – that best represented customer loyalty and would predict company growth. With a renewed interest in patient satisfaction, this survey has been adapted in the healthcare community, but there are no known publications describing its use in a radiation oncology clinic. Materials/Methods From April of 2019 through February of 2022, hard-copy forms were given to patients after CT simulation and at completion of therapy in a private room onsite. The question read, "How likely are you to refer patients who are friends or family to [Institution] Radiation Oncology?" If he or she agreed to answer the survey, the respondent used a Likert scale from 0 to 10 (least to most likely) and added comments in a free-text section. Responses with a 0 to 10 score were logged with no identifying information and were classified as "promoters" (9 to 10) or "detractors" (0 to 6); a monthly Net Promoter Score was calculated by dividing the number of "promoters" by the sum of "promoters" and "detractors." Comments, if available, were additionally transcribed. The scores and comments were shared with the department once weekly in morning huddle. Results Patients filled out 1318 forms (62%). Monthly Net Promoter scores ranged from 94.44 to 100. The average response was 9.74 with marks of 9.76, 9.74, 9.75, and 10.00 for 2019, 2020, 2021, and 2022, respectively. In 2019 and 2020, replies were separated by timepoints of CT simulation (9.73 and 9.71) and after radiotherapy (9.75 and 9.78). During this timeframe, comments were further analyzed by qualitative analysis and were classified into "staff appreciation," "patient feelings/treatment," "wait times," "respect," and "communication." Conclusion The Net Promotor Score is an available tool to get immediate feedback from patients, allowing rapid service recovery, if needed. In our department, scores were consistently favorable with little difference through the COVID-19 pandemic, and patients noted that they were appreciated, felt respected, and experienced short wait times.

The entropy scale factor (ESF) is a novel theory proposing that the scale of time and space change depending on entropy, and that this change underlies special relativity, gravity, and the expansion of space. In special relativity, as the relative velocity of objects increases, there are more possible combinations of momentum and position within the moving frame due to the uncertainty principle. This increase in possible microstates represents an increase in entropy, which can be correlated with the time dilation and length contraction of special relativity. The ESF predicts that an observer in an empty region of space taking measurements near an entropic object will measure time to run more slowly and lengths to appear longer in the direction of entropy. These changes in scale would warp of spacetime, causing gravity. For objects with low acceleration, gravity can be approximated by the time dilation component only. For a single star, this approximation predicts a gravitational field similar to that of Newtonian gravity. For a constellation of stars, the ESF predicts that gravity will be stronger than in Newtonian gravity, because time dilation is added as a scalar sum, instead of the vector sum used in Newtonian gravity. Adding fields as a scalar sum avoids the cancelling out that comes with vectors pointed in different directions, leading to increased gravitational acceleration. This effect could explain galaxy rotation dynamics and the gravitational lensing of galaxies without the need for dark matter. Additionally, the ESF would cause space to expand as the entropy of the universe increases. This is because the entropy of a spherical boundary changes only the radial dimension, so as the entropy encoded on the boundary increases time within the boundary slows down more quickly than the volume decreases. Given the constant speed of light, an observer inside such a boundary will experience the increasing volume to time ratio as the expansion of space. Accordingly, the rapid increase in entropy in the early universe would cause a rapid expansion of space, possibly explaining the homogeneity of the large-scale structure of the universe without the need for inflation. In our recent universe, the increasing rate of entropy production due to black holes may explain the accelerating expansion of space, without the need for dark energy.

Measurements of a black hole’s position are limited in four different ways: Absorption of short-wavelength photons by the black hole, gravitational lensing’s interference with geometric diffraction, gravitational redshift decreasing the resolution of interactions close to the event horizon, and the relatively long wavelength of Hawking radiation. These limitations mean that a black hole cannot be localized more precisely than its Schwarzschild radius. Limitations on measuring mass and velocity mean that the position and momentum of a black hole cannot be simultaneously known more precisely than 2 h r s /l P , a value more restrictive than the Heisenberg uncertainty principle. Hidden information about a black hole’s position and momentum results in many possible microstates that are indistinguishable to an observer. One way to interpret the physical meaning of Bekenstein‐Hawking entropy is as a measure of the number of these microstates. This interpretation allows entropy to be generalized to objects in any gravitational field, because gravitational redshift increases uncertainty about position and momentum for objects in all gravitational fields, not just those of black holes.

In this study, we use measurements from over 4,735 globally distributed Global Navigation Satellite System receivers to track the progression of traveling ionospheric disturbances (TIDs) associated with the 15 January 2022 Hunga Tonga‐Hunga Ha'apai submarine volcanic eruption. We identify two distinct Large Scale traveling ionospheric disturbances (LSTIDs) and several subsequent Medium Scale traveling ionospheric disturbances (MSTIDs) that propagate radially outward from the eruption site. Within 3,000 km of epicenter, LSTIDs of >1,600 km wavelengths are initially observed propagating at speeds of ∼950 and ∼555 ms−1, before substantial slowing to ∼600 and ∼390 ms−1, respectively. MSTIDs with speeds of 200–400 ms−1 are observed for 6 hrs following eruption, the first of which comprises the dominant global ionospheric response and coincides with the atmospheric surface pressure disturbance associated with the eruption. These are the first results demonstrating the global impact of the Tonga eruption on the ionospheric state.

Background:Radiation therapy can cause long-term dysphagia that seriously affects quality of life for survivors of head and neck cancer. This study evaluates a novel organ at risk, the contralateral pharyngeal constrictor muscles, to find out whether radiation dose to this structure predicts late swallowing function in patients with head and neck cancer.Methods:The study included patients with head and neck cancer treated with radiation and concurrent systemic therapy at a single institution over 3 years. One-year dysphagia was defined as either the presence of a gastrostomy tube or an abnormal modified barium swallow ≥ 1 year after completion of radiation.Results:Fifty-five patients met inclusion criteria, of which 46 were alive at 1 year. One-year dysphagia was present in 37% (n = 17) of this population. Contralateral constrictor V60 < 40% was associated with a 1-year dysphagia rate of 6%, compared with 57% in patients with V60 ≥ 40% (P < .001). An uninvolved pharynx mean dose < 45 Gy was associated with a 1-year dysphagia rate of 22%, compared with 52% in patients with an uninvolved pharynx mean dose ≥ 45 Gy (P = .03). Editing the clinical target volume off air cavities was associated with a decrease in 1-year dysphagia from 67% to 12% (P < .001), and with a reduction of contralateral constrictor V60 from 62% to 33% (P < .001). Air cavity editing was not associated with a change in locoregional recurrence or 1-year survival.Conclusions:This is the first study to report a connection between contralateral constrictor dose and late swallowing function. The correlation between air cavity editing and contralateral constrictor V60 suggests that contralateral constrictor dose may depend partly on technique. Further studies are needed to explore whether these findings can be replicated prospectively and in other practice settings.

Abstract Here, we assess to what extent the Empirical Canadian High Arctic Ionospheric Model (E‐CHAIM) can reproduce the climatological variations of vertical Total Electron Content (vTEC) in the Canadian sector. Within the auroral oval and polar cap, E‐CHAIM is found to exhibit Root Mean Square (RMS) errors in vTEC as low 0.4 TECU during solar minimum summer but as high as 5.0 TECU during solar maximum equinox conditions. These errors represent an improvement of up to 8.5 TECU over the errors of the International Reference Ionosphere (IRI) in the same region. At sub‐auroral latitudes, E‐CHAIM RMS errors range between 1.0 and 7.4 TECU, with greatest errors during the equinoxes at high solar activity. This represents an up to 0.5 TECU improvement over the IRI during summer but worse performance by up to 2.4 TECU during the winter. Comparisons of E‐CHAIM performance against in situ measurements from the European Space Agency's Swarm mission are also conducted, ultimately finding behavior consistent with that of vTEC. In contrast to the vTEC results, however, E‐CHAIM and the IRI exhibit comparable performance at Swarm altitudes, except within the polar cap, where the IRI exhibits systematic underestimation of electron density by up to 1.0 × 1011 e/m3. Conjunctions with mid‐latitude ionosondes demonstrate that E‐CHAIM's errors appear to result from compounding same‐signed errors in its NmF2, hmF2, and topside thickness at these latitudes. Overall, E‐CHAIM exhibits strong performance within the polar cap and auroral oval but performs comparably to the IRI at sub‐auroral latitudes.

By transferring energy from pickup ions in a rocket exhaust plume to EM waves in the ionosphere, the first demonstration of rocket exhaust driven amplification (REDA) of whistler mode waves was achieved on 26 May 2020. The source of coherent VLF waves was the Navy NML Transmitter at 25.2 kHz located in La Moore, South Dakota. A region of the topside ionosphere at 480 km altitude was converted into an amplifying medium with a 60 second firing of the Cygnus BT-4 engine. The rocket exhaust was injected as a neutral cloud moving perpendicular to field lines that connected the NML transmitter to the VLF Radio Receiver Instrument (RRI) on e-POP/SWARM-E at 1080 km altitude. Charge exchange between the ambient O+ ions and the hypersonic water molecules in the exhaust produced an active plasma media with H2O+ ions in a ring-beam velocity distribution. The 25.2 kHz VLF signal from NML was amplified by 30 dB for a period 87 seconds as observed with the electric fields measurements by the RRI. A secondary source of coherent ELF waves was amplified by 50 dB relative to a 300 Hz signal before the engine burn. The 300 Hz ELF waves are of unknown origin but they were related to harmonics of 100 Hz recorded by the RRI more the 600 seconds before the Cygnus burn. Extremely strong coherent emissions and quasi-periodic bursts were observed in the 300 to 310 Hz frequency range for 200 seconds after the release. The excitation of a ELF whistler cavity may have lasted longer but the orbit of the SWARM-E/e-POP moved the RRI sensor away from the wave emission region. Propagation analysis suggests that the 25.2 kHz VLF waves are less likely to be trapped in plasmaspheric ducts than the 300 Hz ELF band. The 50 dB amplification of the ELF modes may be the result of multi-hop whistler modes echoing between geomagnetic-conjugate hemispheres, gaining energy by cyclotron resonance with the radiation belt electrons.

Large swathes of the margin of the East Antarctic Ice Sheet experience pronounced surface melting during the austral summer. The nature and temporal evolution of evolving surface hydrological systems are poorly known, however, as are their potential connections with englacial and subglacial water systems and their effects on ice dynamics. We have acquired helicopter-based ground-penetrating radar (GPR), electrical self-potential (SP), broadband passive seismic and GNSS data to delineate the geometry and monitor the temporal evolution of the subsurface hydrological system of the marine-terminating Sørsdal Glacier, Princess Elizabeth Land, East Antarctica, between the austral summers of 2017-18 and 2018-19. Our data reveal the presence of a shallow englacial hydrological system that is connected to surface lakes upstream of the grounding line and, surprisingly, is active not only in the austral summer but also through the Antarctic winter. Here we illustrate the spatial and temporal characteristics of the englacial hydrological system and its susceptibility to tidal forcing through the Antarctic winter. Our observations are consistent with persistent year-round redistribution of mass from grounded to floating portions of at the East Antarctic margin, with far-reaching consequences for ice shelf stability.

S Draft (6 March 2020)