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Whistler‐mode hiss waves are crucial to the dynamics of Earth's radiation belts, particularly in the scattering and loss of energetic electrons and forming the slot region between the inner and outer belts. The generation of hiss waves involves multiple potential mechanisms, which are under active research. Understanding the role of hiss waves in radiation belt dynamics and their generation mechanisms requires analyzing their temporal and spatial evolutions, especially for strong hiss waves. Therefore, we developed an Imbalanced Regressive Neural Network (IR‐NN) model for predicting hiss amplitudes. This model addresses the challenge posed by the data imbalance of the hiss data set, which consists of predominantly quiet‐time background samples and fewer but significant active‐time intense hiss samples. Notably, the IR‐NN hiss model excels in predicting strong hiss waves (>100 pT). We investigate the temporal and spatial evolution of hiss wave during a geomagnetic storm on 24–27 October 2017. We show that hiss waves occur within the nominal plasmapause, and follow its dynamically evolving shape. They exhibit intensifications with 1 and 2 hr timescale similar to substorms but with a noticeable time delay. The intensifications begin near dawn and progress toward noon and afternoon. During the storm recovery phase, hiss intensifications may occur in the plume. Additionally, we observe no significant latitudinal dependence of the hiss waves within |MLAT| < 20°. In addition to describing the spatiotemporal evolution of hiss waves, this study highlights the importance of imbalanced regressive methods, given the prevalence of imbalanced data sets in space physics and other real‐world applications. Plain Language Summary: Whistler‐mode hiss waves play a crucial role in understanding the dynamics of Earth's radiation belts, particularly scattering and loss of energetic electrons and the formation of the slot region. The underlying generation mechanisms of hiss wave sources remain an active area of research, which needs to quantify the global evolution of these waves, especially powerful ones. We developed an Imbalanced Regressive Neural Network (IR‐NN) model, which excels at accurately predicting strong hiss wave activity, that is of particular interest in radiation belt studies. We analyzed the evolution of hiss waves during a geomagnetically active period in October 2017. We found that these waves predominantly occur within the plasmapause boundary and exhibit dynamics that follow the plasmapause's changes. These waves strengthen on timescales similar to those of magnetospheric substorms, with a slight delay, and move to different local times during different phases of the storm. These waves maintain uniform intensity across low to mid‐latitudes. This study underlines the importance of imbalanced regressive methods in handling imbalanced data sets, a common challenge in space physics and related physical science fields. This approach is not only significant for advancing our understanding of space weather phenomena but also has broader implications in other areas. Key Points: An imbalanced regressive neural network model of hiss amplitude developed that predicts quiet‐time background and active‐time intense wavesHiss waves are well organized inside the plasmapause and follow its dynamic shape, evolving from dawn toward later local time during a stormModeled hiss evolution correlates with chorus, supporting the hypothesis that hiss is generated by evolving chorus waves [ABSTRACT FROM AUTHOR]

Whistler mode waves in the plasmasphere and plumes drive significant losses of energetic electrons from the Earth's radiation belts into the upper atmosphere. In this study, we conducted a survey of amplitude‐dependent whistler wave properties and analyzed their associated background plasma conditions and electron fluxes in the plasmasphere and plumes. Our findings indicate that extremely large amplitude (>400 pT) whistler waves (a) tend to occur at L > 4 over the midnight‐dawn‐noon sectors and have small wave normal angles; (b) are more likely to occur during active geomagnetic conditions associated with higher fluxes of anisotropic electrons at 10 s keV energies; and (c) tend to occur at higher latitudes up to 20° with increasing amplitude. These results suggest that extremely large amplitude whistler waves in the plasmasphere and plumes could be generated locally by injected electrons during substorms and further amplified when propagating to higher latitudes. Plain Language Summary: Whistler mode waves are known as one of the primary drivers of precipitating energetic electrons from the Earth's radiation belts into the upper atmosphere. We utilize plasma wave observations from the Van Allen Probes mission and conduct a survey of whistler mode waves inside the plasmasphere and plumes, which are plasma regions surrounding the Earth and filled with high‐density cold electrons. Statistical results indicate that extremely large amplitude whistler waves are more likely to occur at large L shells (L shell is defined as the distance from magnetic field lines to the center of the Earth at the magnetic equator) in the post‐midnight sectors during active geomagnetic conditions associated with high fluxes of tens of keV electrons exhibiting anisotropic pitch angle distributions (with a flux peak in the direction that is perpendicular to the background magnetic field). These waves tend to occur at higher latitudes with increasing amplitude. Results suggest that these waves could be generated locally by injected electrons during substorm activity and may be further amplified when propagating to higher latitudes. Key Points: Van Allen Probes wave measurements are used to statistically analyze the whistler waves in the plasmasphere or plume regionsExtremely large amplitude (>400 pT) whistler waves tend to occur at L shells >4 over 0–18 hr MLT with small wave normal angles (<10°)Larger amplitude whistler waves are observed during more active substorm activities and higher magnetic latitudes [ABSTRACT FROM AUTHOR]

Abstract Whistler mode waves in the plasmasphere and plumes drive significant losses of energetic electrons from the Earth's radiation belts into the upper atmosphere. In this study, we conducted a survey of amplitude‐dependent whistler wave properties and analyzed their associated background plasma conditions and electron fluxes in the plasmasphere and plumes. Our findings indicate that extremely large amplitude (>400 pT) whistler waves (a) tend to occur at L > 4 over the midnight‐dawn‐noon sectors and have small wave normal angles; (b) are more likely to occur during active geomagnetic conditions associated with higher fluxes of anisotropic electrons at 10 s keV energies; and (c) tend to occur at higher latitudes up to 20° with increasing amplitude. These results suggest that extremely large amplitude whistler waves in the plasmasphere and plumes could be generated locally by injected electrons during substorms and further amplified when propagating to higher latitudes.

In the information network, using the characteristics of information diffusion of the Internet, information pushing can be carried out effectively to help publicize safety education, which is of great significance to the construction of safety education system in colleges and universities. In this paper, we optimize the distribution of nodes through graph transformation and independent set ideas and propose an influence maximization algorithm based on HISS to improve the usability of safety information. On this basis, an adaptive safety education system is designed, and an optimization algorithm is proposed for determining the probability of content and knowledge point mastery, which is applied to actual safety education. It was found that the total score of the safety test of the experimental class was improved by 16.22 points before and after, the total score of the experimental class exceeded that of the control class by 10.49 points, and the p-values were all less than 0.001. In total, 84.53% of the students strongly agreed or agreed that the types of learning resources could satisfy their learning needs, and 82.29% of the students were satisfied or very satisfied with the way of pushing the resources of the online course. It indicates that improving the safety education system can increase students’ motivation to learn safety, promote the mastery of safety skills, and cultivate safety awareness.

Însan hîssên xwe bi duanî bi ziman îfade dikin. Hîssên însanan gerdunî ne. Hêrs, hezkirin, şermkirin û hwd. hîssên gerdûnî ne. Lê tiştên ku têne hezikirin an jê tê şermkirin li gor çandan diguhere. Yanê hîs çand-spesîfîk in. Wexta kesek ji zimanekî zêdetir zimanan bizanibe dê hîssên xwe çawa bijî. Gelo ew ê bi zimanê yekem ve an zimanê din ve hîssên xwe bîne ziman? Mijara duzimanîtî û hiss bi vê pirsê dest pê dike. Di vê gotarê de bersiva vê pirsê di çarçoveya duzimanîtîya kurdî-tirkî de hate gerîn. Wekî metod lîteratur hate lêkolîn û li qadê çevdêrî hatine kirin. Bersiva vê pirsa bi zimannasîya tetbîqî ve eleqedar çima dê bersiva gelekî prisên pratîk bide, loma girîng e. Di encama vê xebatê de hate dîtin ku li gor şert û şûrtên duzimanên kurdî-tirkî, îfadekirina hîssan dibe ku bi zimanê yekem an jî bi zimanê duyem baştir û kûrtir bê kirin.

Hiss waves play an important role in removing energetic electrons from Earth’s radiation belts by precipitating them into the upper atmosphere. Compared to plasmaspheric hiss that has been studied extensively, the evolution and effects of plume hiss are less understood due to the challenge of obtaining their global observations at high cadence. In this study, we use a neural network approach to model the global evolution of both the total electron density and the hiss wave amplitudes in the plasmasphere and plume. After describing the model development, we apply the model to a storm event that occurred on 14 May 2019 and find that the hiss wave amplitude first increased at dawn and then shifted towards dusk, where it was further excited within a narrow region of high density, namely, a plasmaspheric plume. During the recovery phase of the storm, the plume rotated and wrapped around Earth, while the hiss wave amplitude decayed quickly over the nightside. Moreover, we simulated the overall energetic electron evolution during this storm event, and the simulated flux decay rate agrees well with the observations. By separating the modeled plasmaspheric and plume hiss waves, we quantified the effect of plume hiss on energetic electron dynamics. Our simulation demonstrates that, under relatively quiet geomagnetic conditions, the region with plume hiss can vary from L = 4 to 6 and can account for up to an 80% decrease in electron fluxes at hundreds of keV at L > 4 over 3 days. This study highlights the importance of including the dynamic hiss distribution in future simulations of radiation belt electron dynamics.

Precipitation into the Earth's atmosphere due to pitch angle scattering by plasma waves has been recognized as one of the major loss mechanisms for energetic electrons. In this study, we quantitatively evaluate their roles in precipitating electrons during a conjunction event with modulated electron precipitation observed at low altitudes by Electron Loss and Fields INvestigation and three types of whistler mode waves (hiss, plume hiss, and chorus) measured near the equator by Time History of Events and Macroscale Interactions during Substorms. Electron precipitation was observed from ∼50 keV to <1 MeV with a spatial modulation, suggested by a good correlation between L shell‐sorted precipitation fluxes and wave intensities. A quasi‐linear analysis supports the observed energy range of precipitation and the ratio of precipitating‐to‐trapped flux. Our findings reveal that the modulated energetic electron precipitation is driven by hiss, plume hiss, and chorus waves. Plain Language Summary: Energetic electrons precipitated from the inner magnetosphere into the upper atmosphere can form diffuse and discrete aurora and modulate the ionospheric conductance. One of the major drivers of electron precipitation is wave‐particle interaction with whistler mode waves. In this study, we use the Electron Loss and Fields INvestigation CubeSats to measure electron precipitation at low altitudes and the Time History of Events and Macroscale Interactions during Substorms to provide wave and plasma measurements near the magnetic equator in the conjugate locations. We find that the electron precipitation rate is highly correlated to the whistler mode wave intensity near the equator. Through a quasi‐linear analysis, we demonstrate that the modulation of electron precipitation is driven by whistler mode hiss, plume hiss, and chorus waves that occur in an extensive region of the Earth's magnetosphere. Key Points: Modulated electron precipitation from tens to hundreds of keV over L shells of 4–9 is observed by Electron Loss and Fields INvestigation at low altitudesA good correlation is observed between the spatial variations of electron precipitation and wave intensities of hiss, plume hiss, and chorusQuasi‐linear modeling based on the observed wave and plasma parameters reproduced the observed electron precipitation [ABSTRACT FROM AUTHOR]

Hepatalin is a hormone secreted by the liver in response to pulses of insulin after a mixed nutrient meal, but only if the liver receives two permissive synergistic feeding signals from the stomach. Hepatalin stimulates glucose uptake and storage as glycogen in skeletal muscle, heart, and kidney but not liver, intestines, or adipocytes. Insulin acts primarily on liver and fat. Reduced hepatalin action results in postprandial hyperglycemia, compensatory elevation of insulin secretion, and a resultant shift in partitioning of nutrient energy storage from glycogen in muscle, to fat. Chronic hepatalin suppression leads to a predictable chronology of dysfunctions, first diagnosable as Absence of Meal-induced Insulin Sensitization (AMIS) which progresses to prediabetes, adiposity, and type 2 diabetes. The focus on nutrient partitioning and the role of hepatalin allows AMIS to be diagnosed, prevented, and treated, including through the use of lifestyle interventions. [ABSTRACT FROM AUTHOR]

Abstract Precipitation into the Earth's atmosphere due to pitch angle scattering by plasma waves has been recognized as one of the major loss mechanisms for energetic electrons. In this study, we quantitatively evaluate their roles in precipitating electrons during a conjunction event with modulated electron precipitation observed at low altitudes by Electron Loss and Fields INvestigation and three types of whistler mode waves (hiss, plume hiss, and chorus) measured near the equator by Time History of Events and Macroscale Interactions during Substorms. Electron precipitation was observed from ∼50 keV to

Previous statistical studies of plasmaspheric hiss investigated the averaged shape of the magnetic field power spectra at various points in the magnetosphere. However, this approach does not consider the fact that very diverse spectral shapes exist at a given L‐shell and magnetic local time. Averaging the data together means that important features of the spectral shapes are lost. In this paper, we use an unsupervised machine learning technique to categorize plasmaspheric hiss. In contrast to the previous studies, this technique allows us to identify power spectra that have "similar" shapes and study their spatial distribution without averaging together vastly different spectral shapes. We show that strong negative correlations exist between the hiss frequency and bandwidth. Key Points: Unsupervised machine learning is used to categorize hiss power spectra of the electric field from Van Allen ProbesFrom the pre‐noon sector toward the afternoon sector the hiss frequency decreases while the bandwidth increasesWe discuss possible source mechanisms that are consistent with the spatial distribution of the hiss waves [ABSTRACT FROM AUTHOR]

We conduct electromagnetic particle simulations in a uniform magnetic environment to verify the nonlinear wave growth process of plasmaspheric hiss in the equatorial plasmasphere. The satisfaction of the separability criterion for coexisting multiple frequency waves in the initial stage of wavenumber‐time evolution declares that wave packets are coherent and capable of growing nonlinearly. Spatial and temporal evolutions of two typical modes located in wavenumber‐time evolution demonstrate the consistency among wave growths, frequency variations, and inhomogeneity factor S in coherent wave packets, showing that rising and falling tones occur at negative and positive S values, respectively, and an obvious wave growth happens in a reasonable range of S satisfying the second‐order resonance condition. Wave packets extracted from wave fields in space and time by a frequency band‐pass filter confirm a good agreement between the nonlinear theory and simulation results. The nonlinear growth rates of the extracted wave packets possess similar magnitudes to the growth rates of wave packets in the simulation, and they are much greater than the theoretical linear growth rate, indicating that the nonlinear process is essential in the generation of plasmaspheric hiss. Plain Language Summary: We have conducted a one‐dimensional electromagnetic particle simulation of whistler‐mode waves instability driven by minor energetic electrons with temperature anisotropy in a uniform magnetic field. We find generation of many short wave packets with rising and falling tone frequencies starting from different frequencies. These wave packets are mostly coherent satisfying the separability criteria in frequency and wavenumbers. Namely, the nonlinear trapping potentials due to coherent wave packets do not overlap each other in the velocity phase space. By applying band‐pass filter, we extracted each wave packet, and calculated the wave amplitude, frequency, the inhomogeneity factor of the second‐order cyclotron resonance, and resonant currents. We find reasonable agreement between the growth rates of the wave packets in the simulation and the theoretical nonlinear growth rates, which are much greater than the linear growth rates. The simulation result confirms that the coherent nonlinear wave growth process due to frequency variation is the essential process in generating whistler‐mode hiss emissions locally in the equatorial plasmasphere. Key Points: Coherent whistler‐mode hiss wave packets can grow from thermal fluctuations in the equatorial plasmasphereNonlinear wave growth processes due to frequency variation take place with the coherent hiss wave packetsThe nonlinear growth rates of hiss with rising and falling tones are much greater than the linear growth rates [ABSTRACT FROM AUTHOR]

Using wave measurements from the EMFISIS instrument onboard Van Allen Probes, we investigate statistically the spatial distributions of the intensity of plasmaspheric hiss waves. To reproduce these empirical results, we establish a fitting model that is a third-order polynomial function of L-shell, magnetic local time (MLT), magnetic latitude (MLAT), and AE*. Quantitative comparisons indicate that the model’s fitting functions can reflect favorably the major empirical features of the global distribution of hiss wave intensity, including substorm dependence and the MLT asymmetry. Our results therefore provide a useful analytic model that can be readily employed in future simulations of global radiation belt electron dynamics under the impact of plasmaspheric hiss waves in geospace.

Recent ray tracing suggests that plasmaspheric hiss can originate from chorus observed outside of the plasmapause. Although a few individual events have been reported to support this mechanism, the number of reported conjugate events is still very limited. Using coordinated observations between Time History of Events and Macroscale Interactions during Substorms (THEMIS) and Van Allen Probes, we report on an interesting event, where chorus was observed at a large L shell (~9.8), different from previously reported events at L

In this paper, we present an optimization mechanism for two popular landmark-based mobile robot visual homing algorithms (ALV and HiSS), called vector pre-assigned mechanism (VPM). VPM contains two branches, both of which can promote the homing performance effectively. In addition, to make the landmark distribution satisfy the equal distance assumption, a landmark optimization strategy is proposed based on imaging principle of the panoramic vision. Experiments on both panoramic image database and a real mobile robot have confirmed the effectiveness of the proposed methods.

Abstract Objectives Vocalization as part of vigilance behaviour is widespread across animal taxa, including ruminants. Calls of wild-living giraffes have never been recorded and spectrographically investigated. This study reports the acoustic structure of vigilance-related hiss and snort calls of wild-living giraffes Giraffa camelopardalis. Results The hiss and snort calls were emitted during five recording sessions produced by nine individual giraffes (8 adults and 1 subadult) in their natural environment in Namibia (3 individuals) and Kenya (6 individuals). These calls attended vigilance behaviour toward humans in hides or in vehicles and cheetahs as natural predators of giraffe young. This study provides spectrographic analyses of 22 hiss and 20 snort calls. The giraffe hisses were broadband vocalizations of an average duration of 0.72 s (from 0.24 to 1.04 s) and a peak frequency of 0.69 kHz. The giraffe snorts were broadband pulsed calls of an average duration of 0.28 s (from 0.13 to 0.55 s), a peak frequency at 0.20 kHz and comprised a prominent low-frequency pulsation of 23.7 pulses/s. The acoustic structure of giraffe hisses is reminiscent of vigilance-related hisses of musk deer Moschus moschiferus. Giraffe snorts differ from snorts of other ruminants by their prominent pulsed pattern.

Lightning generated whistlers (LGWs) play an important role in precipitating energetic electrons in the Earth's inner radiation belt and beyond. Wave burst data from the Van Allen Probes are used to unambiguously identify LGWs and analyze their properties at L < 4 by extending their frequencies down to ~100 Hz for the first time. The statistical results show that LGWs typically occur at frequencies from 100 Hz to 10 kHz with the major wave power below the equatorial lower hybrid resonance frequency, and their wave amplitudes are typically strong at L < 3 with an occurrence rate up to ~30% on the nightside. The lifetime calculation indicates that LGWs play an important role in scattering electrons from tens of keV to several MeV at L < ~2.5. Our newly constructed LGW models are critical for evaluating the global effects of LGWs on energetic electron loss at L < 4. Plain Language Summary: After initial lightning strikes, a type of plasma wave is generated, typically referred to as a lightning generated whistler (LGW), a portion of which can propagate into near‐Earth space. These waves can interact with the trapped energetic electron population in the Earth's radiation belts, causing pitch angle scattering, and thus play an important role in energetic electron loss into the Earth's upper atmosphere. Using high‐resolution wave burst data from the twin Van Allen Probes over the entire Van Allen Probes era (2012–2019), we evaluate the typical properties and global distributions of LGWs. The newly constructed LGW models are used to quantify their global effects on energetic electron loss in the near‐Earth space and indicate that LGWs play an important role in scattering electrons over a broad energy range (tens of keV to several MeV) in the inner radiation belt and beyond. Key Points: Lightning generated whistlers (LGWs) are preferentially observed between 100 Hz and 10 kHz with the majority of wave power below fLHRWave amplitudes of LGWs typically range from a few to tens of pT, peaking at L < 3 on the nightside with an occurrence rate of up to ~30%The newly constructed statistical properties of LGWs are adopted to evaluate their global effects on the radiation belt electron loss [ABSTRACT FROM AUTHOR]

Whistler mode waves are suggested to play a dual role in precipitation loss and acceleration of energetic electrons in Jovian magnetosphere. Using the combined wave data from Juno and Galileo, we constructed global maps of whistler mode waves in the Jovian inner magnetosphere (M‐shell <20). Whistler mode waves are found to be extensively present over M‐shells from 6 to ~13, peaking at ~10, and extend to magnetic latitudes at least up to 50°. Whistler mode wave intensities vary from a few pT to ~100 pT, similar to the intensity level at Earth. The new finding on the latitudinal extension of whistler mode waves indicates their potential effects on electron precipitation over a broad energy range from ~100 eV to several MeV. The newly constructed whistler mode wave spectra are crucial for evaluating the accurate role of whistler mode waves in energetic electron dynamics in the Jovian inner magnetosphere. Plain Language Summary: Whistler mode waves, a type of natural plasma wave with frequencies below electron cyclotron frequency, are known to play an important role in both loss and acceleration processes of energetic electrons in Jovian magnetosphere. However, the global distribution of whistler mode waves in an extensive region, which is critical for evaluating the effects of whistler mode waves on energetic electrons, is not well known. In the present study, we constructed global maps of whistler mode waves in the Jovian inner magnetosphere using plasma wave data from both Juno and Galileo satellites. Our statistical results show that whistler mode waves are extensively present with an intensity ranging from a few picotesla (pT) to ~100 pT, similar to the intensity level at Earth. In particular, Juno wave data newly reveal that whistler mode waves can extend to magnetic latitudes at least up to 50°, implying that whistler mode waves should be effective in scattering electrons into the upper atmosphere over a broad energy range from ~100 electronvolts to several mega‐electronvolts. Whistler mode wave spectra from Juno also provide crucial information for quantifying the role of whistler mode waves in energetic electron dynamics in the Jovian inner magnetosphere. Key Points: Whistler mode waves are extensively present in the Jovian inner magnetosphere peaking at M‐shell ~10Whistler mode waves are observed at magnetic latitudes up to at least ~50°, higher than previously thoughtWhistler mode wave distributions from Juno and Galileo are consistent in the overlapped region with an intensity up to ~100 pT [ABSTRACT FROM AUTHOR]

A comprehensive numerical raytracing study of whistler mode wave power with the inclusion of finite background electron and ion temperature is performed in order to investigate wave power distribution in relation to the plasmapause. Both Landau damping and linear growth of whistler mode waves are taken into account using a bi‐Maxwellian hot electron distribution as well as an isotropic hot electron distribution. Isotropic and bi‐Maxwellian distributions yield similar results of statistical spatial wave power for frequencies below 500 Hz. The effect of finite background temperature of ∼1 eV for electrons and ions are secondary in terms of the spatial distribution of whistler mode waves relative to the plasmapause. Three primary equatorial source locations at L=2, Lpp and L=5, corresponding to within the plasmasphere, at the plasmapause and outside the plasmapause, are investigated for MLT values of 00, 06, 12, and 18. At each location, waves are launched with a range of initial wave normal angles (−70° to 20°). The simulated wave power distributions are compared with observations from the EMFISIS instrument on Van Allen Probe A. Correspondence between the simulated distribution and the observations requires a weighting of the source regions. Results suggest that the majority of whistler mode power in the plasmasphere is sourced from within the plasmasphere itself and near the plasmapause. Only at noon (MLT 12) is wave power sourced primarily from at and outside the plasmapause. Key Points: A comprehensive raytracing study with the inclusion of finite particle temperatureAn isotropic hot electron distribution sufficiently captures the spatial distribution of whistler mode wave powerBulk of the hiss power is generated locally within the plasmasphere for most MLTs [ABSTRACT FROM AUTHOR]

In this paper, using the combined observations of the NOAA 16, LANL-01A, IMAGE satellites, VLF radio wave, and ground-based riometers, we study the fluctuation of lower ionosphere-associated precipitating energetic electrons during a geomagnetic storm on 8 November 2004. Associated with the substorm dispersion injection observed by the LANL-01A satellite, the riometers observed obvious enhancements of ionospheric absorption within the electron isotropic zone, which they attributed to the tail current sheet scattering (TCS) mechanism. Through observations of the NOAA 16 satellite, we found a sharp enhancement of the precipitating electron flux within the anisotropic zone, which entailed an obvious separation of energetic electron precipitation at high latitudes. This energetic electron precipitation within the anisotropic zone leads to the significant enhancement of electron density in the D region, thus resulting in the variations of VLF radio wave amplitudes, which propagate in the middle latitudes. Since the projection of the electron precipitation region within the anisotropic zone is at the inner edge of the plasmapause observed by the IMAGE EUV, the precipitation of energetic electrons should be attributed to the ELF hiss-ring current electron interaction. As a result, the energetic electron precipitations due to the tail current sheet scattering mechanism and wave-particle interaction in the inner magnetosphere were both observed and analyzed as they were associated with a substorm during a geomagnetic storm.

We have conducted an extensive survey of whistler mode hiss emission at Saturn using nearly the complete data set from the Cassini Radio and Plasma Wave Science investigation. We distinguish the hiss emission by frequency and intensity threshold criteria. The survey includes all longitudes and latitudes >25° for r < 10 RS, limited to the availability of plasma density data. The results indicate that hiss intensity is highest at high latitude, and the level of intensity is larger than chorus by at least an order of magnitude. After a rapid increase in intensity starting near L = 13, the hiss intensity remains relatively constant extending to L > 100. The intensity of the hiss as a function of frequency has a shallow peak near 35 Hz but remains always in the range ~5 × 10−5 nT2 < I < ~10−3 nT2. These survey results will be important in modeling the scattering interactions of whistler mode emissions with electrons in the Saturn magnetosphere. Based on recent particle and field observations, sources of Saturn hiss occur on and near the footprints of field‐aligned currents, plasma injections, and reconnected field lines. Key Points: Hiss occurrence and intensity are highest at high latitude and organized in L‐shell, with shallow peak at 35 HzRegions of hiss intensity can identify field lines containing plasma injections, field‐aligned currents, and SKR sourcesIntense hiss at low frequencies suggests a likely strong source of electron scattering at high energies [ABSTRACT FROM AUTHOR]

Whistler mode waves are important for precipitating energetic electrons into Earth's upper atmosphere, while the quantitative effect of each type of whistler mode wave on electron precipitation is not well understood. In this letter, we evaluate energetic electron precipitation driven by three types of whistler mode waves: plume whistler mode waves, plasmaspheric hiss, and exohiss observed outside the plasmapause. By quantitatively analyzing three conjunction events between Van Allen Probes and POES/MetOp satellites, together with quasi‐linear calculation, we found that plume whistler mode waves are most effective in pitch angle scattering loss, particularly for the electrons from tens to hundreds of keV. Our new finding provides the first direct evidence of effective pitch angle scattering driven by plume whistler mode waves and is critical for understanding energetic electron loss process in the inner magnetosphere. We suggest the effect of plume whistler mode waves be accurately incorporated into future radiation belt modeling. Plain Language Summary: Electron precipitation into Earth's upper atmosphere is an important loss mechanism of energetic electrons trapped in the inner magnetosphere. Although whistler mode waves are known to be effective in producing electron precipitation through pitch angle scattering, the relative roles of various whistler mode waves that play in electron losses are unclear. In this letter, we quantitatively analyze conjunction events, where Van Allen Probes observed various whistler mode waves near the equator and Low‐Earth‐Orbiting satellites detected electron precipitation approximately along the same magnetic field line but at low altitudes. By combining the satellite data analysis and quasi‐linear theory, we found that whistler mode waves observed in plumes are very effective in scattering energetic electrons, which are ultimately lost through interacting with the neutral atmosphere. Our new finding provides the direct evidence that plume whistler mode waves play an important role in energetic electron precipitation, which is crucial for understanding energetic electron loss process in the Earth's inner magnetosphere. Key Points: Three types of whistler mode waves are observed during conjunction events between Van Allen Probes and POES/MetOpThese whistler mode waves include plume whistler mode waves, plasmaspheric hiss, and exohissPlume whistler mode waves are very effective in producing energetic electron precipitation (from tens to hundreds of keV) [ABSTRACT FROM AUTHOR]

In this paper, we present an optimization mechanism for two popular landmark-based mobile robot visual homing algorithms (ALV and HiSS), called vector pre-assigned mechanism (VPM). VPM contains two branches, both of which can promote the homing performance effectively. In addition, to make the landmark distribution satisfy the equal distance assumption, a landmark optimization strategy is proposed based on imaging principle of the panoramic vision. Experiments on both panoramic image database and a real mobile robot have confirmed the effectiveness of the proposed methods. [ABSTRACT FROM AUTHOR]

In functional phonology, the commutation test is the only theoretically justifiable analytic procedure that enables us to elicit, identify and establish the phonemes and the archiphonemes of a given language. The purpose of this paper is to demonstrate how, in my view, we can perform the commutation test in order to establish the consonant phonemes and archiphonemes of British English known as RP (Received Pronunciation). To conduct the commutation test, I will proceed with the analysis step by step in order to arrive at the complete system of consonant phonemes and archiphonemes of English. I provide tables of the phonological contents of all the phonemes and archiphonemes established as well as diagrams of the phonematic units so as to show the relationships into which the phonematic units mutually enter. [ABSTRACT FROM AUTHOR]

We survey 3 years (2013–2015) of data from the Van Allen Probes related to plasmaspheric plume crossing events. We detect 194 plume crossing events, and we find that 97% of the plumes are accompanied by very low frequency hiss emissions. The plumes are mainly detected on the duskside or dayside. Careful examination of the hiss spectra reveals that all hiss emissions consist of obvious fine structure. Application of a band‐pass filter reveals that the fine structure is consistent with the occurrence of discrete wave packets. The hiss data display high coherency. The events are classified by location. Duskside hiss and nightside hiss tend to have extremely high polarization with no chorus at the high‐frequency end of the dynamic spectrum. The duskside hiss has a distinct upper frequency limit. On the other hand, the dawnside hiss has strong chorus elements at the upper hiss frequency, which makes the upper frequency limit ambiguous. We show that the structure of whistler mode hiss is different from artificial random noise. Although noise also has fine spectral characteristics, the polarization and waveform data are totally different from the hiss cases. Our results strongly suggest that whistler mode hiss in plasmaspheric plumes universally possesses fine structure. Key Points: We examine 194 plume crossing events observed by the Van Allen ProbesWe observe hiss emissions in 97% of the plume eventsAll hiss emissions have obvious fine structure [ABSTRACT FROM AUTHOR]

Whistler mode waves play a major role in regulating the lifetime of trapped electrons in the Earth’s radiation belts. Specifically, interaction with whistler mode hiss waves is one of the mechanisms that maintains the slot region between the inner and outer radiation belts. The generation mechanism of hiss is a topic still under debate with at least three prominent theories present in the literature. Lightning generated whistlers in their ducted or non-ducted modes are considered to be one of the possible sources of hiss. We present a study of new observations from the Radio Receiver Instrument (RRI) on the Enhanced Polar Outflow Probe (ePOP: also known as SWARM-E). RRI consists of two orthogonal dipole antennas, which enables polarization measurements, when the satellite boresight is parallel to the geomagnetic field. Here we present 105 ePOP - RRI events from 2014−2018, in which lightning whistlers(75) and hiss waves(39) were observed. In more than 50% of those whistler observations, hiss found to co-exist. Moreover, the whistler observations are correlated with observations of wave power at the lower-hybrid resonance. The observations and a whistler mode ray-tracing study suggest that multiple-hop lightning induced whistlers can be a source of hiss and plasma instabilities in the magnetosphere.

Objectives: Vocalization as part of vigilance behaviour is widespread across animal taxa, including ruminants. Calls of wild-living giraffes have never been recorded and spectrographically investigated. This study reports the acoustic structure of vigilance-related hiss and snort calls of wild-living giraffes Giraffa camelopardalis. Results: The hiss and snort calls were emitted during five recording sessions produced by nine individual giraffes (8 adults and 1 subadult) in their natural environment in Namibia (3 individuals) and Kenya (6 individuals). These calls attended vigilance behaviour toward humans in hides or in vehicles and cheetahs as natural predators of giraffe young. This study provides spectrographic analyses of 22 hiss and 20 snort calls. The giraffe hisses were broadband vocalizations of an average duration of 0.72 s (from 0.24 to 1.04 s) and a peak frequency of 0.69 kHz. The giraffe snorts were broadband pulsed calls of an average duration of 0.28 s (from 0.13 to 0.55 s), a peak frequency at 0.20 kHz and comprised a prominent low-frequency pulsation of 23.7 pulses/s. The acoustic structure of giraffe hisses is reminiscent of vigilance-related hisses of musk deer Moschus moschiferus. Giraffe snorts differ from snorts of other ruminants by their prominent pulsed pattern. [ABSTRACT FROM AUTHOR]

Purpose: The hand is one of the most complex and important parts of our body, enabling us to complete an array of necessary functions, from grasping things to expressing ourselves through gestures. Unfortunately, hand trauma sequelae are usually serious as they can disturb daily living and professional tasks, especially in manual workers. Severe hand injuries are mutilating and have a tremendous impact on the mental health of most patients. This study aims to explore the correlation between HISS and DASH scores in hand injuries, shedding light on their utility in evaluating patient outcomes. Methods: We reviewed the medical records of 385 patients suffering from hand injuries, who were admitted to the Department of Orthopedic Surgery and Traumatology of Ibn Sina Hospital of Rabat, between January 2022 and May 2023. The severity of injuries was assessed by the Hand Injury Severity Score (HISS). The impact of these injuries was assessed by the Disabilities of Arm, Shoulder, and Hand score (DASH). Results: This study found a significant correlation between the severity of the hand injury as assessed by the HISS and the functional outcome as evaluated by the DASH score. Conclusion: Patients with high HISS are likely to report higher DASH scores due to the interplay between objective injury severity and subjective functional outcomes, as was reported by several studies.