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The quality of geospatial data collection depends, among other things, on the reliability and efficiency of the GNSS receivers or even better integrated GNSS/INS systems used for positioning. High-precision positioning is currently not only the domain of professional receivers but can also be achieved by using simple devices, including smartphones. This research focused on the quality of 2D and 3D kinematic positioning of different geodetic and low-cost GNSS devices, using the professional mobile mapping system (MMS) as a reference. Kinematic positioning was performed simultaneously with a geodetic Septentrio AsteRx-U receiver, two u-blox receivers—ZED-F9P and ZED-F9R—and a Xiaomi Mi 8 smartphone and then compared with an Applanix Corporation GPS/INS MMS reference trajectory. The field tests were conducted in urban and non-urban environments with and without obstacles, on road sections with large manoeuvres and curves, and under overpasses and tunnels. Some general conclusions can be drawn from the analysis of the different scenarios. As expected, some results in GNSS positioning are subject to position losses, large outliers and multipath effects; however, after removing them, they are quite promising, even for the Xiaomi Mi8 smartphone. From the comparison of the GPS and GNSS solutions, as expected, GNSS processing achieved many more solutions for position determination and allowed a relevant higher number of fixed ambiguities, even if this was not true in general for the Septentrio AsteRx-U, in particular in a surveyed non-urban area with curves and serpentines characterised by a reduced signal acquisition. In GNSS mode, the Xiaomi Mi8 smartphone performed well in situations with a threshold of less than 1 m, with the percentages varying from 50% for the urban areas to 80% for the non-urban areas, which offers potential in view of future improvements for applications in terrestrial navigation.

IEC 62351-4 standard is published to address cybersecurity vulnerabilities of IEC 61850 Manufacturing Message Specification (MMS) messages. This standard includes a set of cipher suites that are recommended for securing MMS messages. However, these are only a set of recommendations. There is no work in the literature that implements them on an IEC 61850 MMS message and reports the performances. In order to fill this importance knowledge gap, this short communication reports results of implementing cipher suites recommended by IEC 62351-4 on IEC 61850 messages. In addition to implementation details, real message exchanges are demonstrated with lab experiments. Finally, changing certificate and message sizes are reported. The results show that cipher suite selection is critical as some suites have 29.67 % smaller certificate size than others. The novelty of this short communication is showing details of IEC 62351 application and relevant changes on message sizes and structures of IEC 61850 MMS messages. There is no similar work or publication showing such procedures and results.

The mobile mapping systems (MMSs) are increasingly used in the Architecture, Engineering and Construction sector (AEC). Their involvement in the digital transition of our cities and built heritage could be a valuable solution in speeding up the scan-to-BIM processes. In this framework, the course “Knowledge of the built heritage in the era of climate change” of Politecnico di Torino offers an innovative approach for MSc degree students in Building Engineering. In fact, it deals with the whole workflow from the surveying activities (data acquisition and processing), to the BIM modelling up to the final digital twin integrated with e.g. sensors data and management information. This contribution describes the case studies of the multidisciplinary course as an application for this methodology, where not only terrestrial laser scanning or UAVs (Unmanned Aerial Vehicles) have been used, but also MMSs have been tested to understand if they could be a suitable option. This paper aims to show the course experience derived from the collaboration of the geomatics and drawing domains along with students’ results and feedback. Moreover, the research underlines the pros and cons of this procedure.

Deneysel çalışmalarda periferik sinirin akson çapı, miyelinli sinir lifi çapı ve miyelinli sinir için iç çap/dış çap oranı (g-ratio), demiyelinizasyon, remiyelinizasyon ve sinir onarımının değerlendirilmesinde görüntü analiz programlarından yararlanılmaktadır. Bu nedenle, morfometrik değerlendirmeye sıklıkla gereksinim duyulan periferik sinir çalışmaları hedeflenerek, laboratuvarımızda yarı otomatik bir görüntü analiz programı geliştirilmiştir. Çalışmamızda, geliştirdiğimiz görüntü analiz yazılımının performansının, serbest erişimli çok amaçlı diğer bir yazılım ile güvenilirlik yönünden karşılaştırılması amaçlanmıştır. Farelerin genel anestezi altında siyatik sinirlerinden alınan doku örnekleri gluteraldehit solüsyonuna alınmıştır. Rutin elektron mikroskop takip yöntemlerinden geçirilerek epoksi resin (epoxy resin) gömülen dokulardan yarı ince kesitler alınmış ve toluidin mavisi ile boyanmıştır. Kesitler dijital kameralı ışık mikroskopta incelenmiş ve X100’lük objektifte fotoğraflanmıştır. Mikrograflar laboratuvarımızda geliştirilen Tantuna Morfometrik Ölçüm Sistemi (TanTuna Morphometric Measuring System; TT-MMS) yazılımı ile analiz edilmiştir. Seçilen iki adet ışık mikrograftan rastgele seçilen 200 adet miyelinli akson kesitinin ölçümleri program kullanılarak yapılmıştır. Aynı ölçümler ImageJ programı ile tekrarlanmış ve her iki programla elde edilen veriler istatistiksel olarak karşılaştırılmıştır. Ek bir donanıma ihtiyaç duymadan her iki yazılımın da güvenilir olduğu ve birbirleriyle uyumlu ölçümler yaptıkları saptanmıştır (p, Image analysing programs are used in peripheral nerve studies to measure axon diameter, myelinated nerve diameter and the ratio of inner axonal diameter to outer diameter (g-ratio), demyelination, remyelination and nerve repair. So, a semi-automatic, image analysis program was developed in our laboratory by targeting peripheral nerve studies which morphometric evaluation is frequently required. It is aimed to compare the performance and reliability of this program with another free access multipurpose software. Tissue samples from sciatic nerves of mice were taken into gluteraldehyde solution under general anesthesia. After routine electron microscopic processing method, semi-thin sections were taken from epoxy resin embedded blocks and stained with toluidine blue. Sections were examined and photographed under the light microscope at X100 magnification. Micrographs were analyzed using the Tantuna Morphometric Measuring System (TT-MMS) software developed in our laboratory. Measurements of the randomly selected 200 myelinated axon sections from two selected light micrograph were performed using the program. The measurements were repeated with ImageJ program and data obtained using both programs were compared statistically. We determined that both softwares are reliable and measurements compatible with each other (p

Magnetosheath jets are localized dynamic pressure enhancements in the magnetosheath. We make use of the high time resolution burst mode data of the Magnetospheric Multiscale mission for an analysis of waves in plasmas associated with three magnetosheath jets. We find both electromagnetic and electrostatic waves over the frequency range from 0 to 4 kHz that can be probed by the instruments on board the MMS spacecraft. At high frequencies we find electrostatic solitary waves, electron acoustic waves, and whistler waves. Electron acoustic waves and whistler waves show the typical properties expected from theory assuming approximations of a homogeneous plasma and linearity. In addition, 0.2 Hz waves in the magnetic field, 1 Hz electromagnetic waves, and lower hybrid waves are observed. For these waves the approximation of a homogeneous plasma does not hold anymore and the observed waves show properties from several different basic wave modes. In addition, we investigate how the various types of waves are generated. We show evidence that, the 1 Hz waves are connected to gradients in the density and magnetic field. The whistler waves are generated by a butterfly-shaped pitch-angle distribution and the electron acoustic waves by a cold electron population. The lower hybrid waves are probably generated by currents at the boundary of the jets. As for the other waves we can only speculate about the generation mechanism due to limitations of the instruments. Studying waves in jets will help to address the microphysics in jets which can help to understand the evolution of jets better.

The region surrounding the reconnection separatrix consists of many particle and wave transient features (electron, cold and hot ion beams, Hall E&B fields, kinetic Alfvén, LH, etc. waves) whose pattern and parameters may vary depending on the distance from active neutral line. We study nine quick MMS entries into the plasma sheet boundary layer (PSBL) from the tail lobe to address the meso-scale pattern and other characteristics of phenomena for active separatrix crossings as deduced from particle observations. The outermost thin layer (a fraction of ion inertial scale, di) of low-density plasma consists of accelerated electron beams and lobe cold ions and displays density depletions (EBL region). It is followed by hot proton beam (PBL region) in which the plasma density grows from lobe-like towards plasma sheet-like values; the beam energy-dispersion is used to estimate the distance from the active neutral line. Thin (usually ≤ di) region containing intense Hall-like Ez perturbations (HR) usually overlaps with EBL and PBL regions. It often includes correlated B perturbations suggesting the Alfvén waverelated transport from the reconnection source; the estimated Alfvénic ratio δE/(VA δB) varied between 0.3 and 1.3 in studied examples. The HR is associated with profound plasma property changes, including the heating of cold ion beams in its innermost part, it hosts intense structured field-aligned currents and intense E-field fluctuations. Surprisingly, most of abovementioned findings are valid for crossings observed at large distances from the reconnection region (exceeding a few tens Re or >100 di) except for longer time-scales and larger spatial scales of the pattern.

Mobile Mapping Systems (MMS) have recently benefited from the development of many fusion-based technologies with countless systems development based on cars, drones, trolley, wearable or portable mapping system. The scale of applicating range from the urban to the architectural scale. Recent solution are also based on visual or Lidar SLAM (Simultaneous Localization and Mapping), which substantially takes advantage of environmental features and techniques of continuous co-registration of the clouds, also in case of absence on GNSS positioning measurement. FARO Technology has recently developed the Swift, a fusion-based hybrid solution that integrates the sensors for 3D mapping in a trolley system configuration and recently, an external camera Panocam Theta Z1 is equipping the system enabling the possibility to associate radiometry to the acquired data. The working principle is the exploitation of a system of static and mobile configuration, using the so-called “anchor scans” co-registration as an hybrid intermediate solution between a typical static scan and a profilometers-based MMS point cloud. The co-registered clouds therefore yield a trajectory mode such as SLAM but benefit from the comparable range and density characteristics, according to user-customized settings, of static scans, with a duration of a few seconds per scan and a few minutes overall. In the present research the Swift System is tested in two different context and the assessment are conducted aimed at satisfying both the urban and the architectural scale instances in the direction of improving further evaluations.

This paper explores the use of Mobile Mapping Systems (MMSs) for urban Cultural Heritage (CH) documentation, which has become an increasingly important tool in surveying for rapid and accurate mapping of both internal and external environments. The study evaluates the performance of the STONEX® X120GO SLAM Laser Scanner, a recent commercial MMS, in documenting CH in various outdoor applications, including urban environments and inaccessible places. The methodology was applied to three test fields in the historic centre of Venice, which include Piazza San Marco, Santa Marta area, and the Venetian canal called Rio de le Toresele. The STONEX® X120GO SLAM Laser Scanner is composed of a 360° rotating head LiDAR scanner, three 5MP cameras, and an Inertial Measurement Unit (IMU) and Global Navigation Satellite System (GNSS) for geospatial 3D point cloud creation. The MMS was evaluated in terms of time, accuracy, and point cloud resolution against other active sensors such as Terrestrial Laser Scanners (TLSs) and spherical photogrammetry. The results suggest that the tested MMS has reached optimal levels of development, enabling high-speed data collection and providing good accuracy for significant urban CH sites. Overall, the paper highlights the importance and potential of MMSs for CH documentation and emphasizes the need for ongoing development to optimize the management process.

Tujuan dan rumusan masalah dari penelitian ini adalah untuk mengetahui apakah dengan pembelajaran matematika menyenangkan siswa (MMS) berbasis metode permainan mathemagic dapat meningkatkan kemampuan komunikasi dan kemandirian siswa. Metode penelitian ini adalah penelitian deskriptif kuantitatif. Penelitian ini dilakukan di SMP Negeri 2 Siborong borong Tahun Pelajaran 2021/2022. Sampel dalam penelitian ini adalah kelas VII-1 sebanyak 36 siswa yang diambil dari jumlah populasi data dan dapat mewakili seluruh populasi dengan teknik pengumpulan sampel yaitu teknik random sampling. Instrumen yang digunakan adalah tes kemampuan komunikasi matematis dan angket dengan teknik analisis data yang dilakukan yaitu dengan menggunakan uji regresi berganda. Berdasarkan hasil dari penelitian ini menghasilkan nilai signifikan sebesar 0.001 < 0.05 dan F hitung 5,366 > F tabel 3,295. Dengan peningkatan kemampuan komunikasi dan kemandirian siswa secara simultan (bersamaan) terhadap variabel Y adalah sebesar 36%. Sehingga dapat disimpulkan bahwa terdapat peningkatan kemampuan komunikasi dan kemandirian siswa melalui pembelajaran matematika menyenangkan siswa (MMS) berbasis metode permainan mathemagic.

PURPOSE: Noxious sensory inputs from the neonatal Intensive Care Unit (NICU) and lack of placental support negatively impact neuronal organization which has implications later in life. Evidence regarding early interventions (EI) on preterm neonates (PN) at high risk for developmental motor disorders is limited and inconclusive. This study focuses on neuromotor changes following Multimodal stimulations (MMS) with sensory and motor interventions among stable hospitalized PNs. METHODS: This single-center, non-blinded pre-test post-test control group study will recruit 60 PNs admitted to the Level II and III NICU of a recognized tertiary care teaching hospital by convenience sampling method into two groups by block randomization. Group A (n = 30) will receive MMS trial lasting for 30 minutes per session for five days per week, until discharge of the neonate from the NICU; Group B (n = 30) will receive regular lifesaving care from the NICU. Anthropometric evaluation, physiological status, and Infant Neurological International Battery (INFANIB) will be the outcome measures used to analyze the neuromotor behavioral modifications among the hospitalized PNs. All the outcome measures will be recorded at baseline, after every five days (to compare trajectories of scores between the groups), and at the end of the intervention at the time of discharge of neonate from the NICU. RESULTS: Demographic and outcome measures will be assessed for their normality using the Shapiro-Wilk test. Within and between-group comparisons will be analyzed by the repeated measures analysis of variance/Friedman test and independent t-test/Mann-Whitney U test respectively. CONCLUSION: MMS, which includes both sensory and motor interventions, will, to the best of the authors’ knowledge, be the first trial for modifying the neuromotor behavior of hospitalized PNs. If successful, the clinical effects of this protocol could be revolutionary in mitigating developmental impairments of PNs.

The MMS satellites encountered a Kelvin-Helmholtz instability (KHI) period in the early non-linear phase at the post-noon flank magnetopause on 8 Sep 2015. The adjacent magnetosheath was characterized by a pre-dominantly northward Bz > 0 magnetic field with weakly positive in-plane components in a GSM coordinate system. Ion velocity distribution functions indicate at least 17 KH vortex intervals with two typically D-shaped ion beam distributions, commonly associated with reconnection exhausts, that stream in both directions along a mostly northward magnetic field at 350–775 km/s with a median 525 km/s ion beam speed. The counter-streaming ion beams are superposed on a core population of slowly drifting magnetosheath ions with a field-aligned 50–200 km/s speed. Each interval lasted no more than 5.25 s with a median duration of 1.95 s corresponding to in-plane spatial scales 3 < ΔS < 22 di assuming a constant 1 di = 61 km ion inertial scale and a tailward VKH∼258 km/s KH vortex propagation speed along the MMS trajectory. The counter-streaming ions are predominantly observed in the warm KH vortex region between the cold magnetosheath proper and the hot isotropic ion temperature of a low-latitude boundary layer as the MMS constellation traverses a KH vortex. The in-plane spatial scales and the locations of the observed counter-streaming ion beams generally agree with the predictions of twice-reconnected magnetic fields at two mid-latitude reconnection (MLR) regions in a two-fluid three-dimensional numerical simulation previously reported for this KH event. MMS typically recorded a higher phase space density of the fast parallel ion beam that we associate with a tailward reconnection exhaust from the southern MLR (SMLR) and a lower phase space density of the fast anti-parallel ion beam that we associate with a tailward reconnection exhaust from the northern MLR (NMLR) of similar speed. This is either consistent with MMS being closer to the SMLR region than the NMLR region, or that the KHI conditions may have favored reconnection in the SMLR region for the observed in-plane magnetosheath magnetic field as predicted by a two-fluid three-dimensional numerical simulation.

The use of moving devices equipped with range- and image-based sensor, generically defined Mobile Mapping systems (MMS), have been quite a disruptive innovation in the development of Geomatics techniques for 3D surveying large indoor-outdoor spaces and offer multiple solutions. The recent expansion of portable devices in the form of trolleys, backpacks, handheld tools largely implements SLAM (Simultaneous Localization and Mapping) algorithms and technology based on both Lidar and/or visual solutions for answering to the positioning and the 3D reconstruction problems. The research on MMS is directed to improve both multi-sensor integration implementation and usability of systems in diversified use contexts and application fields. The aim of the presented research is the evaluation of the potential of the Swift system recently developed by FARO Technologies, that has been fine-tuned for regular and large extent interiors mapping (such as factories, hospitals, airports, offices). The work tries to preliminary investigate the data delivery and usability of the integrated system. This is based on three elements mounted on a sliding trolley moved by the operator walking: the ScanPlan profilometer working for the 2D SLAM mapping, the static TLS Focus S-series, and the smartphone managing the sensors operation and the acquisition progress. The evaluation strategy undertaken will be based on the global and local performance analysis related to the trajectory, the data accuracy, the metric content and consistency. Two test studies belonging to the 20th century. architecture are presented in a preliminary framework of evaluation and validation: a Liberty-style cinema and the Torino Esposizioni Hall B designed in ferrocement by pier Luigi Nervi.

The three spacecraft which constitute the Swarm mission are equipped with the Micro Advanced Stellar Compass (μASC) provided by the Technical University of Denmark (DTU) for attitude determination. Each μASC is comprised of three Camera Head Units (CHUs) for a total of nine cameras on the mission. The CCD sensor inside the CHUs are sensitive to energetic particle irradiation which appear as transient bright pixels dubbed ’Energetic Particle Detections’ (EPDs) on the star field images. For more than five years the μASCs on-board Swarm have transmitted the occurrence of EPDs to ground and thereby effectively added high energy radiation monitoring capabilities to the Swarm mission. The high sensitivity, high sample rate (1-2 Hz), orientation of the camera heads, simultaneous measurements from all three spacecraft and near-polar orbits at an altitude of 450-510 km and allows for continuous and real-time monitoring of the high energy (>65 MeV) proton environment in LEO. This data uncover short and long term changes in particle flux in e.g. the South Atlantic Anomaly (SAA) of relevance for future mission planning. The same radiation monitoring capability exists on NASA’s Magnetospheric Multiscale Mission (MMS) which, due to its highly elliptical orbit, survey the Van Allen radiation belts and detect enhanced radiation levels in the belts associated with geomagnetic storms. Combining data from the μASCs onboard Swarm and MMS provides unique insight into the injection mechanisms and dynamics of very high energy particles which is currently poorly understood. This work presents observations and results using high energy radiation data obtained from the μASC on board ESA’s Swarm mission, from February 2018 to February 2023, in combination with μASC data from MMS.

We apply Fokker-Planck equation to investigate processes responsible for turbulence in space plasma. In our previous studies, we have shown that turbulence in the inertial range of hydromagnetic scales exhibits Markov properties [1,2]. We have also extended this statistical approach on much smaller scales, where kinetic theory should be applied. Namely, we have already obtained the results of the statistical analysis of magnetic field fluctuations in the Earth’s magnetosheath based on the Magnetospheric Multiscale (MMS) mission [3]. Here we compare the characteristics of turbulence behind the bow shock, inside the magnetosheath, and near the magnetopause. We check whether the second order approximation of the Fokker-Planck equation leads to kappa distribution of the probability density function provided that the first Kramers-Moyal coefficient is linear and the second term is quadratic, describing drift and diffusion correspondingly, which is a generalization of Ornstein-Uhlenbeck process. In some cases the power-law distributions are recovered. For moderate scales we have the kappa distributions described by various peaked shapes with heavy tails. In particular, for large values of the kappa parameter this is reduced to the normal Maxellian distribution. The obtained results on kinetic scales could be important for a better understanding of the physical mechanism governing turbulent systems in laboratory and space.Keywords: Kinetic scales, Markov processes, MMS probe, Plasmas, Solar wind, Turbulence.Acknowledgments. This work has been supported by the National Science Centre, Poland (NCN), through grant No. 2021/41/B/ST10/00823.References1. Strumik, M., & Macek, W. M. 2008a, Testing for Markovian character and modeling of intermittency in solar wind turbulence, Physical Review E, 78, 026414, doi=10.1103/PhysRevE.78.026414.2. Strumik, M., & Macek, W. M. 2008b, Statistical analysis of transfer of fluctuations in solar wind turbulence, Nonlinear Processes in Geophysics, 15, 607-613, doi=10.5194/npg-15-607-2008.3. Macek, W. M., Wójcik, D. & Burch, J. L. 2023, Magnetospheric Multiscale observations of Markov turbulence on kinetic scales, arXiv=2211.05098, Astrophysical Journal, https://doi.org/10.3847/1538-4357/aca0a0..

Magnetic reconnection is a fundamental process in collisionless space plasma, and the electron-scale kinetic physics at the X line controls how the magnetic field lines break and reconnect. The four spacecraft of the Magnetospheric Multiscale (MMS) mission encountered an X line of symmetric reconnection in the terrestrial magnetotail on 27 August 2018. Here, we present the electron-scale dynamics and the generalized Ohm’s law (GOL) analysis of this case. Its two-dimensional structure, magnetic topology, and electron streamline map are reconstructed based on a time-independent and inertialess form of electron magnetohydrodynamic (eMHD) equation. We map the electron velocity distribution functions (VDFs) along the MMS trajectories through the X line, covering the two-side inflow and reconnected regions, and the typical electron motions for forming the observed VDFs are also presented. The observed reconnection electric field EM is approximately 2-3 mV/m and predominantly balanced by the spatial gradient of the electron pressure off-diagonal term PeMN, which is mostly contributed by the electron meandering motion at the X line. Our results show the electron-scale dynamics and the associated electron VDFs at an X line and their role in the electron force balance.

On 28th of August 2018 at 5:30 UT, MMS and Cluster were located in the magnetotail at about 16 earth radii (RE). They both suddenly crossed plasma interfaces. Located near the post midnight sector, Cluster transitioned from a cold plasma sheet to a hot plasma sheet associated with a quasi-parallel earthward flow 800 km/s whereas MMS, located at 4 RE duskward of Cluster, transitioned from a similar cold plasma sheet to the lobe region via a very short period in a hot plasma sheet associated with a vortex-like signature. At 05:50 UT MMS returned to a hot plasma sheet and also detected a quasi-parallel earthward flow ~ 400 km/s and increased energetic ion and electron fluxes. We use measurements from both missions during this conjunction to describe the possible large scale dynamics of the magnetotail as well as some associated kinetic processes. Energetic particle (>50keV) measurements from the two missions are compared. Furthermore, at ion scales, we investigate the possible role of ion fire-hose instability in the plasma flow reduction. At electron scales, we analyze fast and slow non linear electrostatic waves propagating tailward which are detected in the so called electron boundary layer as well as in the hot plasma sheet. We discuss their possible generation mechanisms and link with the large scale dynamics of the magnetotail.

We report the MMS observations of the intense spikes of field-aligned current (FAC) produced by magnetic reconnection at the plasma sheet (PS) field lines. The MMS was located tailward of a near-Earth X-line and the most intense spike of FAC with an electric current density of ∼70 nA/m2 was observed near the magnetic separatrix. The FAC structures located deeper in the PS were strongly filamented and consisted of several spikes with a thickness of ∼(1–2)ρe (ρe is the gyroradius of thermal electrons). We found that the FAC in these structures was carried by unmagnetized thermal and suprathermal electron populations (≥ 1 keV), which were ∼(20–80)% of the entire electron population. Strong nonideal electric fields up to ∼100 mV/m were detected in the FAC spike near the magnetic separatrix. The generation of these fields was mainly due to the anomalous resistivity, possibly caused by the electrostatic fluctuations. As a result, a significant energy dissipation of up to 1.3 nW/m3 occurred within the electron-scale FAC structure, which caused an increase in the electron temperature by a factor of two compared with that outside the FAC. Thus, MMS observations demonstrate that during the interval of the active X-line, the outer part of the PS consists of multiple electron-scale FAC layers/filaments in which a significant energy exchange between electrons and fields occurs. To investigate the stability of these filaments and estimate their lifetime, additional observations and theoretical studies are needed.

We consider the problem of fairly allocating a set of indivisible goods among $n$ agents with additive valuations, using the popular fairness notion of maximin share (MMS). Since MMS allocations do not always exist, a series of works provided existence and algorithms for approximate MMS allocations. The current best approximation factor, for which the existence is known, is $(\frac{3}{4} + \frac{1}{12n})$ [Garg and Taki, 2021]. Most of these results are based on complicated analyses, especially those providing better than $2/3$ factor. Moreover, since no tight example is known of the Garg-Taki algorithm, it is unclear if this is the best factor of this approach. In this paper, we significantly simplify the analysis of this algorithm and also improve the existence guarantee to a factor of $(\frac{3}{4} + \min(\frac{1}{36}, \frac{3}{16n-4}))$. For small $n$, this provides a noticeable improvement. Furthermore, we present a tight example of this algorithm, showing that this may be the best factor one can hope for with the current techniques.

The interaction between the solar wind and Earth’s magnetic field results in the formation of a supercritical bow shock. Downstream of this shock wave, the magnetosheath region emerges, in which high-speed plasma flows can be formed. These jets have been connected to several shock and foreshock properties. Moreover, due to their unique properties (i.e., higher density and velocity compared to the ambient flow), they can cause a variety of different phenomena, including magnetopause reconnection, excitation of ULF waves and electron acceleration.In this work, we use Magnetosphere Multiscale (MMS) mission to demonstrate jets’ complex structure by investigating their velocity distribution functions. Specifically, we focus on how their VDFs change over time and on whether they exhibit non-Maxwellian properties. By comparing with the VDFs taken from the background magnetosheath, we show that full particle plasma moments provide an inadequate description of jet plasma properties. Furthermore, we present different metrics to quantify the non-Maxwellian features exhibited by jet observations. Finally, we discuss how the observed kinetic properties of jets may provide insight into jets generation, wave excitation and evolution.

Across the Earth’s magnetopause, magnetic reconnection has been observed as either the anti-parallel and/or component reconnection scenarios. The magnetic reconnection location prediction model known as the Maximum Magnetic Shear model combines these two scenarios and predicts long reconnection lines crossing the dayside magnetopause along a ridge of maximum magnetic shear. The model has been tested and validated and predicts the dayside reconnection location correctly for 84% of the events. Observed magnetic reconnection events for which the model fails share common characteristics, which indicates that for these conditions additional factors have an influence on the location of the dayside reconnection line. One of these specific conditions results in a set of so-called Knee events for which the anti-parallel reconnection region lines up along the draped Interplanetary Magnetic Field (IMF) lines. For these events, magnetic reconnection remains in the anti-parallel reconnection region as long as it is crossed by the draped IMF. Compared to the usual events, this effect results in a deflection of the connection points between the anti-parallel and component reconnection regions (known as anchor points). This study investigates if the location of the entire component reconnection line or only the anchor points are affected by this deflection. Using two Knee events with confirmed magnetic reconnection location observed by MMS, this study describes how the entire component reconnection line across the dayside magnetopause is deflected if the relative magnetic shear between the maximum magnetic shear location and the deflected magnetic shear location is less than ~5°.

Magnetic field gradients determine magnetic topological structure and current density in space plasma turbulence. This study uses multi-point method analyze high-quality field and plasma data measured by the Magnetospheric Multiscale (MMS) mission in the turbulent magnetosheath. The statistical properties of the curvature of the magnetic field line and the geometric invariant of the magnetic field gradient tensor are further investigated. The results show that the probability distribution function of curvature has two scaling laws. There is a correlation between large curvatures and pressure anisotropy, indicating the acceleration due to curvature drifts. During strong magnetic field, flux ropes and tubes are the most possible magnetic structures. Statistics in the plane formed by geometrical invariants show that about 23% are force free structures consist of 20.5% flux tubes and 79.5% flux ropes. The remaining actively evolved structures are comprised of 30% flux tubes and 70% flux ropes. Moreover, the conditional average of current density and Lorentz force decomposition in geometrical invariants plane are conducted. Results show that flux ropes carried more current density than flux tubes for same geometrical invariants, and flux ropes tend to associate with magnetic pressure force and flux tubes tend to associate with magnetic tension.

The Earth’s magnetosheath is a dynamic region and its properties strongly depend on the angle between the bow shock normal and the solar wind magnetic field (θbn). If the shock is quasi-parallel (θbn < 45°), the magnetosheath is magnetically connected to the foreshock, causing strong fluctuations and structures propagating from upstream to downstream. A quasi-perpendicular shock (θbn > 45°) produces a less structured and more stationary magnetosheath characterized by compression and high ion temperature anisotropy. These distinct configurations make it possible to study how different plasma environments affect various processes such as turbulence, heating, and wave-particle interactions. Therefore, such studies require an accurate classification of the magnetosheath. This is not easily achieved, especially close to the magnetopause where the shock crossing for the plasma of interest cannot be observed.Previously, Karlsson et al. (2021) used data from the Cluster mission to propose a promising classification method using local measurements of the magnetic field standard deviation, high-energy ion flux, and ion temperature anisotropy. In this work, we are building on this study and extending it to the Magnetospheric Multiscale (MMS) mission, having a different orbit than Cluster. We compare this local classification to θbn estimated from upstream conditions and well-known bow shock models, and discuss the advantages and disadvantages of the different methods. Reference: Karlsson, T., Raptis, S., Trollvik, H., & Nilsson, H. (2021). Classifying the magnetosheath behind the quasi-parallel and quasi-perpendicular bow shock by local measurements. Journal of Geophysical Research: Space Physics, 126, e2021JA029269.

The dynamics of Earth's outer electron radiation belt is, in part, driven by interactions with whistler-mode chorus waves. Chorus can cause rapid acceleration of electrons up to relativistic energies, as well as drive precipitation of particles into the atmosphere causing both microbursts and diffuse aurora. Chorus can propagate in such a way that it crosses the plasmapause boundary and may contribute to the possible sources of plasmaspheric hiss, which itself can cause atmospheric losses of particles and the formation of the slot region between the inner and outer radiation belts. The direction of the wave vector relative to the background magnetic field is a key parameter for quantifying these processes, since it determines the propagation trajectory of the wave, and is required for calculating the resonance condition of the wave-particle interaction.The orientation of the wave vector is investigated using both survey mode data and high-resolution burst mode observations from the EMFISIS Waves instrument on the Van Allen Probes spacecraft. Spatial coverage beyond the Van Allen Probes orbit is provided by burst-mode observations from the FIELDS instrument suite on Magnetospheric Multiscale (MMS). The polar and azimuthal wave vector angles are considered using both spectral analysis, where the frequency-time structure can be resolved, and instantaneous values, which can be used to identify variations within individual chorus subpackets. We compare the results from each of these different timescales. Near strong plasma density gradients, such as those which occur on the boundaries of plasmaspheric plumes, we identify that the wave vector becomes more oblique than the general case where no density gradients are present. The obliquity of the wave vector is shown to directly relate to both the magnitude of the density gradient, and its proximity to the spacecraft.

The magnetosheath is a region downstream of the bow shock filled with turbulent, decelerated solar wind plasma which is flowing earthwards. This solar wind flow sometimes shows signatures of localized structures with enhanced dynamic pressure, so called magnetosheath jets. These jets are often associated with low angles between the bow shock normal and the interplanetary magnetic field (IMF) direction, the so called quasi-parallel bow shock. Less often they are also found behind the quasi-perpendicular bow shock.As jets propagate through the magnetosheath, they interact with the surrounding plasma. Studying waves inside, and in the vicinity of, jets is a step towards understanding the interaction of jets with the surrounding plasma. So far whistler waves, electrostatic waves, waves in the lower hybrid frequency range as well as low frequency waves have been reported. However, the sources of these waves are unknown. In addition, further types of waves may be associated with the jets.We conduct a study on waves in magnetosheath jets using burst mode data of the Magnetospheric Multiscale (MMS) mission. The magnetic and electric field data are provided with a sampling rate of 8 kHz, while previous studies used data sets with much lower sampling rates. The high time resolution allows us to study different waves over a large frequency range and investigate properties of these waves. In addition, we discuss possible generation mechanisms.

Tujuan dari penelitian ini adalah untuk mengetahui pengaruh Performance Appraisal, Work Discipline dan Compensation terhadap Kinerja Karyawan melalui Motivasi sebagai variabel intervening di PT. Sampel dalam penelitian ini sebanyak 265 karyawan. Metode analisis data menggunakan SEM-PLS dengan software Smart PLS 2.0. Hasil penelitian menunjukkan bahwa penilaian kinerja berpengaruh terhadap motivasi, variabel penilaian kinerja diketahui memiliki pengaruh yang signifikan terhadap motivasi sebesar 0,309 atau 30,9%, sedangkan variabel penilaian kinerja berpengaruh signifikan terhadap kinerja karyawan sebesar 0,184. Variabel disiplin kerja juga berpengaruh signifikan terhadap kinerja karyawan, yaitu 0,362 atau 36,2%. Dan variabel kompensasi juga memiliki efek signifikan pada motivasi, yaitu 0,503 atau 50,3%. Namun, variabel kompensasi terhadap kinerja karyawan sebesar 0,166 atau 16,6% tidak berpengaruh signifikan, sedangkan variabel motivasi berpengaruh signifikan yaitu 0,239 atau 23,9%. Dapat disimpulkan bahwa Disiplin Kerja dan Motivasi memiliki pengaruh yang signifikan. Dapat disimpulkan bahwa Kompensasi memiliki pengaruh tidak langsung dibandingkan dengan Penilaian Kerja dan Disiplin Kerja terhadap kinerja karyawan melalui Motivasi. Nilai R kuadrat untuk variabel motivasi adalah 0, 552 atau 55, 2%. Nilai R Square untuk variabel kinerja karyawan yang diperoleh adalah 0,621 atau 62,1%. Hasil tersebut menunjukkan bahwa Penilaian Kinerja, Disiplin Kerja, dan Kompensasi secara keseluruhan berpengaruh sebesar 62,1% terhadap Kinerja Karyawan.

We study the problem of allocating indivisible chores to agents under the Maximin share (MMS) fairness notion. The chores are embedded on a graph and each bundle of chores assigned to an agent should be connected. Although there is a simple algorithm for MMS allocations of goods on trees, it remains open whether MMS allocations of chores on trees always exist or not, which is a simple but annoying problem in chores allocation. In this paper, we introduce a new method for chores allocation with connectivity constraints, called the group-satisfied method, that can show the existence of MMS allocations of chores on several subclasses of trees. Even these subcases are non-trivial and our results can be considered as a significant step to the open problem. We also consider MMS allocations of chores on cycles where we get the tight approximation ratio for three agents. Our result was obtained via the linear programming (LP) method, which enables us not only to compute approximate MMS allocations but also to construct tight examples of the nonexistence of MMS allocations without complicated combinatorial analysis. These two proposed methods, the group-satisfied method and the LP method, have the potential to solve more related problems.

In this study, we examine particle energization and injections that show energetic electron enhancements at both MMS in the magnetotail and Van Allen Probes in the inner magnetosphere. Observing injections along with a corresponding flow burst allows us to better understand injections overall. Searching for suitable events, we found that only a small number of events at MMS had corresponding injections that penetrated far enough into the inner magnetosphere to observe with Van Allen Probes. With the four suitable events we did find, we compared the energy spectra at the two spacecraft and mapped the boundary of where the injection entered the inner magnetosphere. We found that, among these injections in the inner magnetosphere, the electron flux did not increase above ∼400 keV, similar to previous results, but the corresponding signatures in the tail observed increased fluxes at 600 keV or higher. There does not appear to be a comparable flux increase at Van Allen Probes and MMS for a given event. None of our injections included ion enhancements at Van Allen Probes, but one included an ion injection at geosynchronous orbit in the GOES spacecraft. All of our injections were dispersed at Van Allen Probes, and we were therefore able to map an estimate of the injection boundary. All of the injections occurred in the premidnight sector. Although we found some events where particle energizations in the tail are accompanied by inner magnetospheric injections, we do not find a statistical link between the two.

IntroductionRetinitis pigmentosa (RP) is a group of neurodegenerative retinopathies causing blindness due to progressive and irreversible photoreceptor cell death. The alkylating agent methyl methanesulfonate (MMS) can induce selective photoreceptor cell death, which is used to establish RP animal models. MMS induces DNA base damage by adding alkyl groups to DNA, and epigenetic modifications influence DNA damage response. Here, we aimed to explore the relationship between DNA methylation and DNA damage response in dying photoreceptors of RP.MethodsThe mouse RP model was established by a single intraperitoneal injection of MMS. The retinal structure and function were assessed by H&E, OCT, TUNEL, and ERG at several time points. The expression of DNA methylation regulators was assessed by qPCR and Western blot. DNMT inhibitor 5-aza-dC was applied to inhibit the activity of DNA methyltransferases and improve the retinal photoreceptor damage.ResultsThe outer nuclear layer (ONL) and IS/OS layer were significantly thinner and the retinal function was impaired after MMS treatment. The cell death was mainly located in the ONL. The retinal damage induced by MMS was accompanied by hyperexpression of DNMT3A/3B. The application of DNMT inhibitor 5-aza-dC could suppress the expression level of DNMT3A/3B, resulting in the remission of MMS-induced photoreceptor cell damage. The ONL and IS/OS layers were thicker than that of the control group, and the retinal function was partially restored. This protective effect of 5-aza-dC was associated with the down-regulated expression of DNMT3A/3B.ConclusionThese findings identified a functional role of DNMT3A/3B in MMS-induced photoreceptor cell damage and provided novel evidence to support DNMTs as potential therapeutic targets in retinal degenerative diseases.Graphical Abstract

Electron heating at collisionless shocks in space is a combination of adiabatic heating due to large-scale electric and magnetic fields and non-adiabatic scattering by high-frequency fluctuations. The scales at which heating happens hints to what physical processes are taking place. In this letter, we study electron heating scales with data from the Magnetospheric Multiscale (MMS) spacecraft at Earth's quasi-perpendicular bow shock. We utilize the tight tetrahedron formation and high-resolution plasma measurements of MMS to directly measure the electron temperature gradient. From this, we reconstruct the electron temperature profile inside the shock ramp and find that the electron temperature increase takes place on ion or sub-ion scales. Further, we use Liouville mapping to investigate the electron distributions through the ramp to estimate the deHoffmann-Teller potential and electric field. We find that electron heating is highly non-adiabatic at the high-Mach number shocks studied here. Plain Language Summary Shock waves appear whenever a supersonic medium, such as a plasma, encounters an obstacle. The plasma, which consists of charged ions and free electrons, is heated by the shock wave through interactions with the electromagnetic fields. In this work, we investigate how electrons are heated at plasma shocks. A key parameter to electron heating is the thickness of the layer where the heating takes place. Here, we use observations from the four Magnetospheric Multiscale spacecraft that regularly cross the standing bow shock that forms when the supersonic plasma, known as the solar wind, encounters Earth's magnetic field. We find that the thickness of the shock is larger than previously reported and is on the scales where ion physics dominate. We also find that the electron heating deviates significantly from simple adiabatic heating.

Fixed-wing Unmanned Aerial Vehicles (UAV) and wearable or portable Mobile Mapping Systems (MMS) are two widely used platforms for point cloud acquisition with Light Detection And Ranging (LiDAR) sensors. The two platforms acquire from distant viewpoints and produce complementary point clouds, one describing predominantly horizontal surfaces and the other primarily vertical. Thus, the registration of the two data is not straightforward. This paper presents a test of targetless registration between a UAV LiDAR point cloud and terrestrial MMS surveys. The case study is a vegetated hilly landscape characterized by the presence of a structure of interest; the UAV acquisition allows the entire area to be acquired from above, while the terrestrial MMS acquisitions will enable the construction of interest to be detailed. The paper describes the survey phase with both techniques. It focuses on processing and registration strategies to fuse the two data together.Our approach is based on the ICP (Iterative Closest Point) method by exploiting the data processing algorithms available in the Heron Desktop post-processing software for handling data acquired with the Heron Backpack MMS instrument. Two co-registration methods are compared. Both ways use the UAV point cloud as a reference and derive the registration of the terrestrial MMS data by finding ICP matches between the ground acquisition and the reference cloud exploiting only a few areas of overlap. The two methods are detailed in the paper, and both allow us to complete the co-registration task.

We search for simultaneous crossings of the Earth’s magnetosheath (MSH) region from ESA’s Cluster and NASA’s MMS missions. We inspect Cluster summary plots to determine the Cluster-MSH crossings. Then, MMS summary plots are inspected, and the MMS-MSH intervals which overlap in time with the Cluster-MSH intervals, are catalogued. We find 117 simultaneous Cluster and MMS magnetosheath crossings in 2017-2021. We are interested in the correlation between magnetosheath properties and bow shock (BS) characteristics. Thus, for each one of the MSH intervals in our catalogue, we determine the BS type. Depending on the angle between the interplanetary magnetic field (IMF) and the BS normal direction, the bow shock can be classified as either quasi-parallel or quasi-perpendicular. OMNI data are used to determine the IMF orientation, and the BS normal direction is estimated using two different approaches: (1) using the minimum variance analysis of the magnetic field and (2) using a bow shock model parameterized with concurrent OMNI data. We will present our catalogue of simultaneous Cluster and MMS magnetosheath crossings, and discuss our estimates for the BS type associated with each crossing., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

This study presents new observations of fine structure and motion of the bow shock formed in the solar wind, upstream of the Earth's magnetosphere. NASA's Magnetospheric Multiscale (MMS) mission has recorded data during 11 encounters with a shock oscillating with frequency of 1 mHz. Shocks move with a speed of 4–17 km s−1; have thickness of 100 km, i.e. an ion gyroradius; and represent cascades of compressional magnetic field and plasma density structures of increasing frequencies or smaller spatial scales. Induced density gradients initiate chains of cross-field current-driven instabilities that heat solar wind ions by the stochastic Ẽ×B wave energisation mechanism. The theoretical ion energisation limits are confirmed by observations. We have identified the ion acceleration mechanism operating at shocks and explained double-beam structures in the velocity space. The nature of this mechanism has been revealed as a stochastic resonant acceleration (SRA). The results provide for the first time a consistent picture of a chain of plasma processes that generate collisionless shocks and are responsible for particle energisation.

The Kelvin-Helmholtz instability (KHI) is a velocity shear driven instability and is considered one of the main candidates for energy and momentum transfer across Earth’s magnetopause. In its linear stage it forms sinusoidal surface waves (KHWs) that travel anti-sunward along the magnetopause. These waves can develop into large-scale rolled-up vortices (KHVs) along the flanks and efficiently mix plasmas from the two sides of the boundary. In this study, we report the first in-situ observations of KHWs and KHVs during southward interplanetary magnetic field (IMF) conditions from MMS data.

Dataoutputfrom 2-D Hybridsimulations for ''Examining the necessary condition for the second-harmonic generation of EMIC waves: MMS observations and 2-D hybrid simulation''. Data are all '.mat' files which can be loaded into theworkspace of Matlab or Octave directly.Please use the latest version of the data. If you have questionsplease contactxue.zx@whu.edu.cn Descriptions of the contents in the mat file: xmax,zmax: length of the simulation domain in each dimension nx,nz:number of cells in each dimension time: time series bx, by, and bz: magnetic field fluctuations normalized to the background magnetic field, size(bx)=size(by)=size(bz)=[nz, nx, numel(time)]

Collisionless shocks play a key role in the heliosphere at planetary bow shocks by governing the conversion of the upstream bulk kinetic energy of the solar wind flow to other forms of energy in the downstream, including bulk plasma heat, acceleration of particles, and magnetic energy. Here we present the first observational identification of the velocity-space signature of shock-drift acceleration of ions at a perpendicular collisionless shock, previously predicted using kinetic numerical simulations, using a field-particle correlation analysis of Magnetospheric Multiscale (\emph{MMS}) observations of Earth's bow shock. Furthermore, by resolving the ion energization rates as a function of particle velocity, the field-particle correlation technique facilitates a clean quantitative separation of the energization rate of the reflected ions from that of the incoming ion beam, enabling a more complete characterization of the energy conversion at the shock.

We use multiple spacecraft measurements of magnetic field and current density by the Magnetospheric Multiscale (MMS) mission in order to reconstruct the magnetic field in the vicinity of sites of magnetic reconnection in space. These reconstructions can show the motion of the spacecraft relative to the X line and have revealed electron scale features such as secondary reconnection. Reconstructions for several events will be shown., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The evolution of plasma entropy and the process of plasma energy re-distribution at the collisionless plasma shock front are evaluated based on the high temporal resolution data from the four MMS spacecraft during the crossing of the terrestrial bow shock. The ion distribution function has been separated into the populations with different characteristic behavior in the vicinity of the shock: the upstream core population, the reflected ions; the gyrating ions; the ions trapped in the vicinity of the shock, and the downstream core population. The values of ion and electron moments (density, bulk velocity, and temperature) have been determined separately for these populations. It was shown that the solar wind core population bulk velocity slows down mainly in the ramp with the electrostatic potential increase but not in the foot region as it was supposed. The reflected ion population determine the foot region properties, so that the proton temperature peak in the foot region is the effect of the relative motion of the different ion populations, rather than an actual increase in the thermal speed of any of the ion population. The ion entropy evaluated showed a significant increase across the shock the enhancement of the ion entropy occurs in the foot of the shock front and at the ramp, where the reflected ions are emerging in addition to the upstream solar wind ions, the anisotropy growing to generate the bursts of ion-scales electrostatic waves. The entropy of electrons across the shock doesn't show significant change - electron heating goes almost adiabatically.