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This short article highlights unsolved problems of magnetic reconnection in collisionless plasma. Advanced in-situ plasma measurements and simulations have enabled scientists to gain a novel understanding of magnetic reconnection. Nevertheless, outstanding questions remain concerning the complex dynamics and structures in the diffusion region, cross-scale and regional couplings, the onset of magnetic reconnection, and the details of particle energization. We discuss future directions for magnetic reconnection research, including new observations, new simulations, and interdisciplinary approaches. [ABSTRACT FROM AUTHOR]

We present observations on 24 April 2023 by the Magnetospheric Multiscale spacecraft at the dayside, mid‐latitude magnetopause, when an interplanetary magnetic cloud (MC) with sub‐Alfvénic flows and northward and dawnward interplanetary magnetic field components impacted Earth's magnetosphere. The aim is to reveal the processes of solar wind‐magnetosphere interaction under sub‐Alfvénic solar wind with northward magnetic field. Our analysis of electron and ion data suggests that magnetopause reconnection occurred near both polar cusps, forming boundary layers on closed magnetic field lines on both the solar wind (i.e., MC) and magnetospheric sides of the magnetopause. Grad‐Shafranov, electron‐magnetohydrodynamics, and polynomial reconstructions of magnetopause current layers show that local (equator‐of‐the‐cusp) reconnection occurred in a sub‐ion‐scale magnetopause current sheet with a low magnetic shear angle (30°). Interestingly, the local reconnection was observed between the two (MC‐side and magnetosphere‐side) layers of closed field lines. It indicates that reconnected field lines from double cusp reconnection were interacting to induce another reconnection at the mid‐latitude magnetopause. Our results suggest that magnetopause reconnection was more efficient or frequent under sub‐Alfvénic solar wind with much lower beta plasma conditions than typical conditions. We discuss the role of such efficient reconnection in the formation of low‐latitude boundary layers. Plain Language Summary: Solar wind is a supersonic plasma flow emanating from the Sun. On rare occasions, the solar wind at 1 AU can be slower than the Alfvén speed, the speed of transverse electromagnetic waves that propagate in magnetized fluids. Such a sub‐Alfvénic solar wind was observed on 24 April 2023 when a magnetic cloud (MC) with intense magnetic fields, associated with a coronal mass ejection, impinged on Earth's magnetosphere. Interestingly, the MC contained northward interplanetary magnetic field (IMF) components; the way in which sub‐Alfvénic solar wind interacts with Earth's magnetosphere for such IMF conditions is more poorly understood than for southward IMF conditions. In this study, we present observations on this day by NASA's Magnetospheric Multiscale (MMS) spacecraft around the dayside magnetopause, the front‐side boundary of the magnetosphere where the solar wind‐magnetosphere interaction processes occur. Our analysis of MMS data shows that magnetic reconnection at the magnetopause, the plasma physical process shaping and transporting solar wind plasma into the magnetosphere, was more efficient than under normal super‐Alfvénic solar wind conditions. This more efficient reconnection under sub‐Alfvénic solar wind with northward IMF can cause complex interaction of reconnected magnetic field lines and may contribute to more vigorous plasma transport. Key Points: Observations by the Magnetospheric Multiscale mission and reconstruction of magnetopause reconnection under sub‐Alfvénic solar windElectron and ion signatures of dual reconnection near the polar cusps for northward and dawnward interplanetary magnetic field conditionsAdditional reconnection at boundary equatorward of the cusp between closed field lines from dual reconnection and those in magnetosphere [ABSTRACT FROM AUTHOR]

Undifferentiated pleomorphic sarcoma (UPS) is the largest subgroup of soft tissue sarcomas. This study determined the value of perfusion-weighted imaging with dynamic-contrast-enhancement (PWI/DCE) morphologic, qualitative, and semiquantitative features for predicting UPS pathology-assessed treatment effect (PATE). This retrospective study included 33 surgically excised extremity UPS patients with pre-surgical MRI. Volumetric tumor segmentation from PWI/DCE was obtained at Baseline (BL), Post-Chemotherapy (PC), and Post-Radiation Therapy (PRT). The surgical specimens’ PATE separated cases into Responders (R) (≥ 90%, 16 patients), Partial-Responders (PR) (89 − 31%, 10 patients), and Non-Responders (NR) (≤ 30%, seven patients). Seven semiquantitative kinetic parameters and maps were extracted from time-intensity curves (TICs), and 107 radiomic features were derived. Statistical analyses compared R vs. PR/NR. At PRT, 79% of R displayed a “Capsular” morphology (P = 1.49 × 10-7), and 100% demonstrated a TIC-type II (P = 8.32 × 10-7). 80% of PR showed “Unipolar” morphology (P = 1.03 × 10-5), and 60% expressed a TIC-type V (P = 0.06). Semiquantitative wash-in rate (WiR) was able to separate R vs. PR/NR (P = 0.0078). The WiR radiomics displayed significant differences in the first_order_10 percentile (P = 0.0178) comparing R vs. PR/NR at PRT. The PWI/DCE TIC-type II curve, low WiR, and “Capsular” enhancement represent PRT patterns typically observed in successfully treated UPS and demonstrate potential for UPS treatment response assessment. [ABSTRACT FROM AUTHOR]

There is ample evidence for magnetic reconnection in the solar system, but it is a nontrivial task to visualize, to determine the proper approaches and frames to study, and in turn to elucidate the physical processes at work in reconnection regions from in-situ measurements of plasma particles and electromagnetic fields. Here an overview is given of a variety of single- and multi-spacecraft data analysis techniques that are key to revealing the context of in-situ observations of magnetic reconnection in space and for detecting and analyzing the diffusion regions where ions and/or electrons are demagnetized. We focus on recent advances in the era of the Magnetospheric Multiscale mission, which has made electron-scale, multi-point measurements of magnetic reconnection in and around Earth's magnetosphere. [ABSTRACT FROM AUTHOR]

Various physical processes in association with magnetic reconnection occur over multiple scales from the microscopic to macroscopic scale lengths. This paper reviews multi-scale and cross-scale aspects of magnetic reconnection revealed in the near-Earth space beyond the general global-scale features and magnetospheric circulation organized by the Dungey Cycle. Significant and novel advancements recently reported, in particular, since the launch of the Magnetospheric Multi-scale mission (MMS), are highlighted being categorized into different locations with different magnetic topologies. These potentially paradigm-shifting findings include shock and foreshock transient driven reconnection, magnetosheath turbulent reconnection, flow shear driven reconnection, multiple X-line structures generated in the dayside/flankside/nightside magnetospheric current sheets, development and evolution of reconnection-driven structures such as flux transfer events, flux ropes, and dipolarization fronts, and their interactions with ambient plasmas. The paper emphasizes key aspects of kinetic processes leading to multi-scale structures and bringing large-scale impacts of magnetic reconnection as discovered in the geospace environment. These key features can be relevant and applicable to understanding other heliospheric and astrophysical systems. [ABSTRACT FROM AUTHOR]

Osteoporosis is one of the most common bone diseases in the elderly. Osteoporosis related bone fracture could seriously lower the quality of the elderly’s life. Thus, in this study, natural products which can treat or prevent osteoporosis without severe side effects have been searched. The ethanol extract of Paeonia lactiflora Pall (Paeoniceae) significantly increased the differentiation of MC3T3-E1 preosteoblastic cells determined by alkaline phosphatase assay. The bioassay-guided isolation of ethyl acetate fraction allowed to isolated 6 paeoniflorin derivatives and 2 catechins such as 4-O-methyl-moudanpioside C (1), 4-O-methylbenzoyloxypaeoniflorin (2), oxypaeoniflorin (3), (+)-catechin (4), catechuic acid (5), paeoniflorin (6), benzoylpaeoniflorin (7), albiflorin (8). Among them, 4-O-methylmoudanpioside C (1), 4-O-methylbenzoyloxypaeoniflorin (2), oxypaeoniflorin (3), benzoylpaeoniflorin (7) and albiflorin (8) significantly increased the ALP activity. Particularly, 4-O-methylmoudanpioside C (1), 4-O-methylbenzoyloxypaeoniflorin (2) were the most active. Furthermore, 4-O-methylbenzoyloxypaeoniflorin (2) significantly inhibited the osteoclastic differentiation of Raw264.7 cells. Taken together, the extract of Paeonia lactiflora and its active constituents, particularly, 4-O-methylbenzoyloxypaeoniflorin (2) could have a benefical effect on bone formation and promote bone health. [ABSTRACT FROM AUTHOR]

We present in‐depth analysis of three southward‐moving meso‐scale (ion‐to magnetohydrodynamic‐scale) flux transfer events (FTEs) and subsequent crossing of a reconnecting magnetopause current sheet (MPCS), which were observed on 8 December 2015 by the Magnetospheric Multiscale spacecraft in the subsolar region under southward and duskward magnetosheath magnetic field conditions. We aim to understand the generation mechanism of ion‐scale magnetic flux ropes (ISFRs) and to reveal causal relationship among magnetic field structures, electromagnetic energy conversion, and kinetic processes in magnetic reconnection layers. Results from magnetic field reconstruction methods are consistent with a flux rope with a length of about one ion inertial length growing from an electron‐scale current sheet (ECS) in the MPCS, supporting the idea that ISFRs can be generated through secondary reconnection in an ECS. Grad‐Shafranov reconstruction applied to the three FTEs shows that the FTEs had axial orientations similar to that of the ISFR. This suggests that these FTEs also formed through the same secondary reconnection process, rather than multiple X‐line reconnection at spatially separated locations. Four‐spacecraft observations of electron pitch‐angle distributions and energy conversion rate j·E′=j·E+ve×B $\mathbf{j}\cdot {\mathbf{E}}^{\prime }=\mathbf{j}\cdot \left(\mathbf{E}+{\mathbf{v}}_{\mathrm{e}}\times \mathbf{B}\right)$ suggest that the ISFR had three‐dimensional magnetic topology and secondary reconnection was patchy or bursty. Previously reported positive and negative values of j·E′ $\mathbf{j}\cdot {\mathbf{E}}^{\prime }$, with magnitudes much larger than expected for typical MP reconnection, were seen in both magnetosheath and magnetospheric separatrix regions of the ISFR. Many of them coexisted with bi‐directional electron beams and intense electric field fluctuations around the electron gyrofrequency, consistent with their origin in separatrix activities. Plain Language Summary: Magnetic reconnection is a physical process that converts magnetic energy into plasma energy by changing the connectivity of magnetic field lines from one region to another. Magnetic reconnection at the outer boundary of planetary magnetospheres, known as the magnetopause (MP), is key to the entry of solar wind plasma and energy into the magnetospheres that forms the basis for space weather phenomena in the magnetospheres. MP reconnection often occurs in a transient or patchy manner, forming magnetic flux ropes (FRs) with helical field lines of various sizes. They may become an important pathway for fast coupling between the solar wind and magnetosphere. However, the generation mechanism of a subclass of FRs, relatively small "ion‐scale" FRs, is poorly understood. Computer simulations show that they are formed in thin and elongated current sheets of single active reconnection site, but this scenario has not been confirmed by observations. Our observations based on NASA's Magnetospheric Multiscale mission show that ion‐scale FR can form in a thin current sheet of single ongoing reconnection site at Earth's MP. The observed FR showed signatures of complex field line connectivity and localized conversion from electromagnetic to electron energy and vice versa, indicating complex MP dynamics. Key Points: Ion‐scale magnetic flux rope (ISFR) can be generated from reconnecting electron‐scale current sheet at the subsolar magnetopause (MP)Preceding mesoscale flux ropes had axial directions akin to that of the ISFR in the MP, suggesting the same generation mechanismThe ISFR had complex magnetic topology with three‐dimensional effects and involved patchy, intense energy conversion in separatrix regions [ABSTRACT FROM AUTHOR]

Pc5 ultralow frequency waves are important for transferring energy between the magnetosphere and ionosphere. While many observations have been performed on Pc5 waves properties, it has been difficult to determine the source region, signal propagation path, and the two‐dimensional structure of Pc5 waves beyond coverage by a small number of satellites. Pc5 waves often show a dawn‐dusk asymmetry, but the cause of the asymmetry is under debate. To address these issues, we used conjunction events between the THEMIS satellites and all‐sky imagers and analyzed two Pc5 wave events that were stronger on the dawnside. For both events, the Pc5 waves propagated from dawnside magnetopause toward the nightside magnetosphere. The Pc5 waves were also associated with dawnside magnetopause surface waves, which were probably induced by the Kelvin‐Helmholtz instability. The ionospheric equivalent currents identified multiple vortices on the dawnside associated with quasi‐periodic auroral arcs and much weaker perturbations on the duskside. Global auroral imaging also presented a similar dawn‐dusk asymmetry with multiple arcs on the dawnside, while only one or two major arcs existed on the duskside. Pc5 waves in the magnetosphere had an anti‐phase relation between the total magnetic field and thermal pressure, with a slower propagation velocity compared with magnetohydrodynamic waves. The Poynting flux was anti‐sunward with an oscillating field‐aligned component. These properties suggest that Pc5 waves were slow or drift mirror mode waves coupled with standing Alfven waves. The ground‐based and multi‐satellite observations provide crucial information for determining the Pc5 waves properties, possible source region, and signal propagation path. Plain Language Summary: Pc5 ultralow frequency waves (1.66–6.66 mHz) are large‐scale waves in space, and Pc5 waves are capable of interacting with particles and modulating higher frequency waves, resulting in energy transfer in the magnetosphere‐ionosphere system. However, it is difficult to find the exact signal propagation path and identify the source due to the limited sparse satellite observations in space. We investigated two Pc5 wave events by using the conjunctions of ground magnetometers, all‐sky imagers, and Time History of Events and Macroscale Interaction During Substorms (THEMIS) satellites. We found that the aurora shows periodic intensification and the ionospheric currents had multiple vortices with dawn‐dusk asymmetry. The Pc5 waves in the magnetosphere are identified as standing waves that were coupled with surface waves at the magnetopause traveling anti‐sunward. We suggest that magnetopause surface waves were induced by Kelvin‐Helmholtz instability and drive the Pc5 waves. The dawn‐dusk asymmetry of Kelvin‐Helmholtz instability in the magnetosheath may explain the current asymmetric pattern in the ionosphere. Key Points: Two Pc5 wave events we analyzed were highly dawn‐dusk asymmetric, with stronger magnetic field perturbations on the dawnside than dusksideSlow or drift mirror mode waves coupled with standing Alfven waves in the magnetosphere were driven by the magnetopause surface wavesSurface waves by Kelvin‐Helmholtz instability along the magnetopause is suggested to be the source of the dawnside Pc5 waves [ABSTRACT FROM AUTHOR]

Purpose: To identify clinically significant genomic copy number (CNV) and single nucleotide variants (SNV) in males with unexplained spermatogenic failure (SPGF). Materials and methods: Peripheral blood DNA from 97/102 study participants diagnosed with oligozoospermia, severe oligozoospermia, or non-obstructive azoospermia (NOA) was analyzed for CNVs via array comparative genomic hybridization (aCGH) and SNVs using whole-exome sequencing (WES). Results: Of the 2544 CNVs identified in individuals with SPGF, > 90% were small, ranging from 0.6 to 75 kb. Thirty, clinically relevant genomic aberrations, were detected in 28 patients (~ 29%). These included likely diagnostic CNVs in 3/41 NOA patients (~ 7%): 1 hemizygous, intragenic TEX11 deletion, 1 hemizygous DDX53 full gene deletion, and 1 homozygous, intragenic STK11 deletion. High-level mosaicism for X chromosome disomy (~ 10% 46,XY and ~ 90% 47,XXY) was also identified in 3 of 41 NOA patients who previously tested normal with conventional karyotyping. The remaining 24 CNVs detected were heterozygous, autosomal recessive carrier variants. Follow-up WES analysis confirmed 8 of 27 (30%) CNVs (X chromosome disomy excluded). WES analysis additionally identified 13 significant SNVs and/or indels in 9 patients (~ 9%) including X-linked AR, KAL1, and NR0B1 variants. Conclusion: Using a combined genome-wide aCGH/WES approach, we identified pathogenic and likely pathogenic SNVs and CNVs in 15 patients (15%) with unexplained SPGF. This value equals the detection rate of conventional testing for aneuploidies and is considerably higher than the prevalence of Y chromosome microdeletions. Our results underscore the importance of comprehensive genomic analysis in emerging diagnostic testing of complex conditions like male infertility. [ABSTRACT FROM AUTHOR]

We present observations in Earth's magnetotail by the Magnetospheric Multiscale spacecraft that are consistent with magnetic field annihilation, rather than magnetic topology change, causing fast magnetic‐to‐electron energy conversion in an electron‐scale current sheet. Multi‐spacecraft analysis for the magnetic field reconstruction shows that an electron‐scale magnetic island was embedded in the observed electron diffusion region (EDR), suggesting an elongated shape of the EDR. Evidence for the annihilation was revealed in the form of the island growing at a rate much lower than expected for the standard X‐type geometry of the EDR, which indicates that magnetic flux injected into the EDR was not ejected from the X‐point or accumulated in the island, but was dissipated in the EDR. This energy conversion process is in contrast to that in the standard EDR of a reconnecting current sheet where the energy of antiparallel magnetic fields is mostly converted to electron bulk‐flow energy. Fully kinetic simulation also demonstrates that an elongated EDR is subject to the formation of electron‐scale magnetic islands in which fast but transient annihilation can occur. Consistent with the observations and simulation, theoretical analysis shows that fast magnetic diffusion can occur in an elongated EDR in the presence of nongyrotropic electron effects. We suggest that the annihilation in elongated EDRs may contribute to the dissipation of magnetic energy in a turbulent collisionless plasma. Plain Language Summary: Magnetic reconnection in electric current sheets is the key to fast release of magnetic energy in many space and astrophysical plasma systems, such as during magnetospheric substorms and solar flares. Establishing the mechanism by which magnetic energy is converted to particle energy in the reconnection process is the key to understanding the large‐scale impacts of reconnection, including energy partition and particle acceleration. It is generally believed that an electron‐scale diffusion region (EDR), where a magnetic‐to‐electron energy conversion occurs, has an X‐type magnetic field geometry around which the energy of antiparallel magnetic fields injected into the EDR is mostly converted to the bulk‐flow energy of electrons by magnetic tension of reconnected field lines. Contrary to this standard X‐type magnetic field geometry of reconnection, we report observations in Earth's magnetotail by NASA's Magnetospheric Multiscale spacecraft showing that the EDR can be highly elongated. The important and surprising consequence of the observed elongated shape of the EDR is that the fast energy conversion in the EDR can be caused mostly by magnetic field annihilation, rather than magnetic topology change. The fast collisionless annihilation that we discovered is fundamentally different from the classical magnetic field annihilation due to collisional and wave‐induced resistivity. Key Points: Multi‐spacecraft observations consistent with magnetic field annihilation in an electron diffusion region (EDR) of magnetotail reconnectionMagnetic field reconstruction suggests that an electron‐scale magnetic island was embedded in the EDR with elongated shapeTheoretical analysis shows that fast collisionless magnetic diffusion can occur in the elongated part of EDR with nongyrotropic electrons [ABSTRACT FROM AUTHOR]

Coulomb collisions provide plasma resistivity and diffusion but in many low-density astrophysical plasmas such collisions between particles are extremely rare. Scattering of particles by electromagnetic waves can lower the plasma conductivity. Such anomalous resistivity due to wave-particle interactions could be crucial to many processes, including magnetic reconnection. It has been suggested that waves provide both diffusion and resistivity, which can support the reconnection electric field, but this requires direct observation to confirm. Here, we directly quantify anomalous resistivity, viscosity, and cross-field electron diffusion associated with lower hybrid waves using measurements from the four Magnetospheric Multiscale (MMS) spacecraft. We show that anomalous resistivity is approximately balanced by anomalous viscosity, and thus the waves do not contribute to the reconnection electric field. However, the waves do produce an anomalous electron drift and diffusion across the current layer associated with magnetic reconnection. This leads to relaxation of density gradients at timescales of order the ion cyclotron period, and hence modifies the reconnection process. It is suggested that waves can provide both diffusion and resistivity that can potentially support the reconnection electric field in low-density astrophysical plasmas. Here, the authors show, using direct spacecraft measurements, that the waves contribute to anomalous diffusion but do not contribute to the reconnection electric field. [ABSTRACT FROM AUTHOR]

On 6 July 2017, the four Magnetospheric Multiscale spacecrafts were positioned within an electron diffusion region (EDR) just northward of a reconnection X line. The EDR was identified by electron crescent distributions, out-of-plane current, and energy conversion. From this position, the three spacecrafts closest to the X line (within about three electron inertial lengths) were able to accurately measure the reconnection electric field and the electron inflow velocity. The reconnection rates derived from the electric field and inflow velocity measurements agree with theoretical estimates (0.11–0.17) and a previous measurement of EM in a tail reconnection event on 11 July 2017. [ABSTRACT FROM AUTHOR]

In‐situ spacecraft missions are powerful assets to study processes that occur in space plasmas. One of their main limitations, however, is extrapolating such local measurements to the global scales of the system. To overcome this problem at least partially, multi‐point measurements can be used. There are several multi‐spacecraft missions currently operating in the Earth's magnetosphere, and the simultaneous use of the data collected by them provides new insights into the large‐scale properties and evolution of magnetospheric plasma processes. In this work, we focus on studying the Earth's magnetopause (MP) using a conjunction between the Magnetospheric Multiscale and Cluster fleets, when both missions skimmed the MP for several hours at distant locations during radial interplanetary magnetic field (IMF) conditions. The observed MP positions as a function of the evolving solar wind conditions are compared to model predictions of the MP. We observe an inflation of the magnetosphere (∼0.7 RE), consistent with magnetosheath pressure decrease during radial IMF conditions, which is less pronounced on the flank (<0.2 RE). There is observational evidence of magnetic reconnection in the subsolar region for the whole encounter, and in the dusk flank for the last portion of the encounter, suggesting that reconnection was extending more than 15 RE. However, reconnection jets were not always observed, suggesting that reconnection was patchy, intermittent or both. Shear flows reduce the reconnection rate up to ∼30% in the dusk flank according to predictions, and the plasma β enhancement in the magnetosheath during radial IMF favors reconnection suppression by the diamagnetic drift. Key Points: Simultaneous observations of the equatorial subsolar magnetopause and dusk flank during time‐extended radial interplanetary magnetic fieldThe magnetosphere enlarges ∼0.7 RE in the subsolar region but <0.2 RE in the flank due to the reduced pressure exerted by the solar windSimultaneous reconnection evidence in the subsolar and flank regions more than 15 RE apart is observed during part of the encounter [ABSTRACT FROM AUTHOR]

Objective: Stillbirths occur 10–20 times more frequently in low‐income settings compared with high‐income settings. We created a methodology to define the proportion of stillbirths that are potentially preventable in low‐income settings and applied it to stillbirths in sites in India and Pakistan. Design: Prospective observational study. Setting: Three maternity hospitals in Davangere, India and a large public hospital in Karachi, Pakistan. Population: All cases of stillbirth at ≥20 weeks of gestation occurring from July 2018 to February 2020 were screened for participation; 872 stillbirths were included in this analysis. Methods: We prospectively defined the conditions and gestational ages that defined the stillbirth cases considered potentially preventable. Informed consent was sought from the parent(s) once the stillbirth was identified, either before or soon after delivery. All information available, including obstetric and medical history, clinical course, fetal heart sounds on admission, the presence of maceration as well as examination of the stillbirth after delivery, histology, and polymerase chain reaction for infectious pathogens of the placenta and various fetal tissues, was used to assess whether a stillbirth was potentially preventable. Main outcome measures: Whether a stillbirth was determined to be potentially preventable and the criteria for assignment to those categories. Results: Of 984 enrolled, 872 stillbirths at ≥20 weeks of gestation met the inclusion criteria and were included; of these, 55.5% were deemed to be potentially preventable. Of the 649 stillbirths at ≥28 weeks of gestation and ≥1000 g birthweight, 73.5% were considered potentially preventable. The most common conditions associated with a potentially preventable stillbirth at ≥28 weeks of gestation and ≥1000 g birthweight were small for gestational age (SGA) (52.8%), maternal hypertension (50.2%), antepartum haemorrhage (31.4%) and death that occurred after hospital admission (15.7%). Conclusions: Most stillbirths in these sites were deemed preventable and were often associated with maternal hypertension, antepartum haemorrhage, SGA and intrapartum demise. Most stillbirths are preventable by better care for women with hypertension, growth restriction and antepartum haemorrhage. Most stillbirths are preventable by better care for women with hypertension, growth restriction and antepartum haemorrhage. [ABSTRACT FROM AUTHOR]

An important process affecting solar wind–Earth's magnetosphere coupling is nonsteady dayside magnetic reconnection, observationally evidenced by a flux transfer event (FTE) that shows a bipolar variation of the magnetic field component normal to the magnetopause. FTEs often consist of two interlinked flux tubes, but, local kinetic processes between the flux tubes are not understood in the context of the FTE structuring, evolution, and impact. An FTE observed by the Magnetospheric Multiscale mission on 2017 December 18 consisted of two flux tubes of different topology. One includes field lines with ends connected to the northern and southern hemispheres while the other includes field lines with both ends connected to the magnetosheath. Reconnection occurring at the flux-tube interface indicates how interacting flux tubes evolve into a flux rope with helical magnetic topology that is either closed or open. This study demonstrates a new aspect of how micro- to meso-scale dynamics occurring within FTEs determines their macroscale characteristics and evolution. [ABSTRACT FROM AUTHOR]

Summary: Pre‐operative anaemia (haemoglobin < 13.0 g.dl−1) is a modifiable peri‐operative risk‐factor. This is screened for using formal laboratory testing. A non‐invasive finger‐probe sensor that can accurately measure haemoglobin is a possible alternative. This study considers the accuracy of non‐invasive haemoglobin measurement using the Rad‐67™ Rainbow (Masimo Corp., Irvine, CA, USA) compared with formal laboratory testing and its usefulness in detecting pre‐operative anaemia. A total of 392 patients had measurements taken for non‐invasive haemoglobin and perfusion index values using the Rad‐67 Rainbow, alongside further peri‐operative parameters and a formal laboratory haemoglobin test. Bland–Altman and sensitivity analysis showed that the limits of agreement between non‐invasive and formal laboratory haemoglobin testing were between −1.95 g.dl−1 and 2.23 g.dl−1 (p < 0.001). The overall performance of non‐invasive haemoglobin measurement was better in men than women (ROC 91.1% vs. 78.2%) and less biased in men, mean −0.08 (SD 1.09, 95%Cl −0.23–0.07) compared with women (mean 0.38 (SD 0.99, 95%CI 0.24–0.52)). Pre‐operative anaemia was more prevalent in women than men (50.3% vs. 14.4%). The sensitivity of non‐invasive anaemia detection (haemoglobin < 13 g.dl−1) was 66% for women and 52% for men. A non‐invasive haemoglobin value of 14.0 g.dl−1 had an overall 91% sensitivity for detecting pre‐operative anaemia (82% in men and 93% in women). The Rad‐67 Rainbow is inadequate for the estimation of formal laboratory haemoglobin and lacks sensitivity for detecting pre‐operative anaemia, especially in women. Further advancement in technology and accuracy is needed before it can be recommended as a routine pre‐operative screening test. [ABSTRACT FROM AUTHOR]

Summary: Pre‐operative anaemia (haemoglobin < 13.0 g.dl−1) is a modifiable peri‐operative risk‐factor. This is screened for using formal laboratory testing. A non‐invasive finger‐probe sensor that can accurately measure haemoglobin is a possible alternative. This study considers the accuracy of non‐invasive haemoglobin measurement using the Rad‐67™ Rainbow (Masimo Corp., Irvine, CA, USA) compared with formal laboratory testing and its usefulness in detecting pre‐operative anaemia. A total of 392 patients had measurements taken for non‐invasive haemoglobin and perfusion index values using the Rad‐67 Rainbow, alongside further peri‐operative parameters and a formal laboratory haemoglobin test. Bland–Altman and sensitivity analysis showed that the limits of agreement between non‐invasive and formal laboratory haemoglobin testing were between −1.95 g.dl−1 and 2.23 g.dl−1 (p < 0.001). The overall performance of non‐invasive haemoglobin measurement was better in men than women (ROC 91.1% vs. 78.2%) and less biased in men, mean −0.08 (SD 1.09, 95%Cl −0.23–0.07) compared with women (mean 0.38 (SD 0.99, 95%CI 0.24–0.52)). Pre‐operative anaemia was more prevalent in women than men (50.3% vs. 14.4%). The sensitivity of non‐invasive anaemia detection (haemoglobin < 13 g.dl−1) was 66% for women and 52% for men. A non‐invasive haemoglobin value of 14.0 g.dl−1 had an overall 91% sensitivity for detecting pre‐operative anaemia (82% in men and 93% in women). The Rad‐67 Rainbow is inadequate for the estimation of formal laboratory haemoglobin and lacks sensitivity for detecting pre‐operative anaemia, especially in women. Further advancement in technology and accuracy is needed before it can be recommended as a routine pre‐operative screening test. [ABSTRACT FROM AUTHOR]

Electron inflow and outflow velocities during magnetic reconnection at and near the dayside magnetopause are measured using satellites from NASA's Magnetospheric Multiscale (MMS) mission. A case study is examined in detail, and three other events with similar behavior are shown, with one of them being a recently published electron‐only reconnection event in the magnetosheath. The measured inflow speeds of 200–400 km/s imply dimensionless reconnection rates of 0.05–0.25 when normalized to the relevant electron Alfvén speed, which are within the range of expectations. The outflow speeds are about 1.5–3 times the inflow speeds, which is consistent with theoretical predictions of the aspect ratio of the inner electron diffusion region. A reconnection rate of 0.04 ± 25% was obtained for the case study event using the reconnection electric field as compared to the 0.12 ± 20% rate determined from the inflow velocity. Key Points: Electron inflow velocities are determined for reconnection at the magnetopause and in the magnetosheathFor four events inflow velocities of 200–400 km/s imply normalized reconnection rates of 0.05–0.25Reconnection rates using electron inflow velocities (0.12) and the reconnection electric field (0.04) are compared for one event Plain Language Summary: When the solar wind impacts the Earth's magnetosphere, an explosive energy conversion process called magnetic reconnection opens the door for solar wind energy to enter the magnetosphere by interconnection of the magnetic fields of the solar wind and of Earth. In this process, magnetic energy is converted to charged‐particle energy. Magnetic reconnection is fairly well understood at large scales and even down to the ion scale. However, the breaking and linking of field lines and the acceleration of electrons occur at much smaller scales, which are only recently being accessed by the NASA Magnetospheric Multiscale mission. This paper analyzes the speed at which electrons flow into and out of reconnection sites. The inflow speeds are crucial because they provide a measurement of the rate at which reconnection proceeds. [ABSTRACT FROM AUTHOR]

At the Earth's low‐latitude magnetopause, clear signatures of the Kelvin‐Helmholtz (KH) waves have been frequently observed during periods of the northward interplanetary magnetic field (IMF), whereas these signatures have been much less frequently observed during the southward IMF. Here, we performed the first 3‐D fully kinetic simulation of the magnetopause KH instability under the southward IMF condition. The simulation demonstrates that fast magnetic reconnection is induced at multiple locations along the vortex edge in an early nonlinear growth phase of the instability. The reconnection outflow jets significantly disrupt the flow of the nonlinear KH vortex, while the disrupted turbulent flow strongly bends and twists the reconnected field lines. The resulting coupling of the complex field and flow patterns within the magnetopause boundary layer leads to a quick decay of the vortex structure, which may explain the difference in the observation probability of KH waves between northward and southward IMF conditions. Plain Language Summary: Space between planets is filled with ionized gas released from the upper atmosphere of the Sun, called the solar wind. Although the Earth's magnetic field basically acts as a barrier to prevent energetic solar wind from penetrating into the region filled with the Earth's magnetic field, called the magnetosphere, it is known that the solar wind frequently leaks into the magnetosphere. The Kelvin‐Helmholtz (KH) instability, which is a flow‐driven instability and can be unstable by the antisunward flowing solar wind, has been considered as an important candidate process for the solar wind leaks. However, past spacecraft observations have revealed that the observation probability of KH waves is very low when the magnetic field in the solar wind, called the interplanetary magnetic field (IMF), is oriented southward, that is, opposite from the Earth's magnetic field. In this study, based on a plasma kinetic simulation, it is found that when the IMF is southward, magnetic reconnection, which is an explosive plasma process that rearranges the magnetic topology across the boundary, occurs at multiple locations in the KH waves and rapidly destroys the wave structures. This may explain the low observation probability of the KH waves under the southward IMF. Key Points: Three‐dimensional fully kinetic simulation of Kelvin‐Helmholtz instability at the Earth's magnetopause under the southward IMF condition is performedFast reconnection causes a rapid decay of the nonlinear vortex structure in the early nonlinear growth phase of the instabilityThe vortex decay can lead to a lower probability of observing magnetopause Kelvin‐Helmholtz waves/vortices during southward IMF periods [ABSTRACT FROM AUTHOR]

Canine cloning is occasionally accompanied by abnormal sexual development. Some male donor cells produce cloned pups with female external genitalia and complete male gonadal dysgenesis, which is classified as an XY disorder of sex development (XY DSD). In this study, we examine the potential of 5-aza-2'-deoxycytidine (5-aza-dC), a DNA methyltransferase inhibitor, to reduce the phenotypic abnormality XY DSD in somatic cell nuclear transfer (SCNT)- derived pups. We used a 9-year-old normal male German Shepherd dog as a cell donor. Donor cells were treated with 10 nM 5-aza-dC for 4 days before being used for SCNT. At the same stage of cell development, significantly lower levels of DNA methylation of the sex-determining region Y (SRY) promoter was observed in the treated donor cells compared to that in the untreated cells (95.2% versus 53.3% on day 4 for the control and treated groups, respectively). No significant differences were observed in the control or treatment groups concerning fusion rate, pregnancy rate (30 days or entire period), the number of pups, or the incidence of XY DSD. However, more XY DSD dogs were observed in the control group (31.25%) than in the treatment group (14.29%). Hypermethylation of the SRY promoter was observed in the XY DSD cloned pups in both the treatment (84.8%) and control groups (91.1 ± 1.4%) compared to the methylation level in the phenotypically normal male pups of the treatment (23.2 ± 20.9%) and control groups (39.1 ± 20.1%). These results suggest that 5-aza-dC treatment of donor cells can reduce the methylation level of the SRY promoter in donor cells, and thus, 5-aza-dC is advantageous for reducing the incidence of XY DSD in canine cloning. [ABSTRACT FROM AUTHOR]

Magnetopause Kelvin‐Helmholtz (KH) waves are believed to mediate solar wind plasma transport via small‐scale mechanisms. Vortex‐induced reconnection (VIR) was predicted in simulations and recently observed using NASA's Magnetospheric Multiscale (MMS) mission data. Flux Transfer Events (FTEs) produced by VIR at multiple locations along the periphery of KH waves were also predicted in simulations, but detailed observations were still lacking. Here we report MMS observations of an FTE‐type structure in a KH wave trailing edge during KH activity on 5 May 2017 on the dawnside flank magnetopause. The structure is characterized by (1) bipolar magnetic BY variation with enhanced core field (BZ) and (2) enhanced total pressure with dominant magnetic pressure. The cross‐section size of the FTE is found to be consistent with vortex‐induced flux ropes predicted in the simulations. Unexpectedly, we observe an ion jet (VY); electron parallel heating, ion, and electron density enhancements; and other signatures that can be interpreted as a reconnection exhaust at the FTE central current sheet. Moreover, pitch angle distributions of suprathermal electrons on either side of the current sheet show different properties, indicating different magnetic connectivities. This FTE‐type structure may thus alternatively be interpreted as two interlaced flux tubes with reconnection at the interface as reported by Kacem et al. (2018) and Øieroset et al. (2019s). The structure may be the result of interaction between two flux tubes, likely produced by multiple VIR at the KH wave trailing edge, and constitutes a new class of phenomenon induced by KH waves. Key Points: We present an MMS observation of a Flux Transfer Event‐type structure during a KH event on the dawn flank magnetopause beyond the terminatorIts characteristics are consistent with a structure produced from multiple vortex‐induced reconnection X‐linesReconnection signatures are found at the central current sheet while properties on either side indicate two flux tubes that interlace [ABSTRACT FROM AUTHOR]

We report the observation of solar wind‐magnetosphere‐ionosphere interactions using a series of flux transfer events (FTEs) observed by Magnetospheric MultiScale (MMS) mission located near the dayside magnetopause on 18 December 2017. The FTEs were observed to propagate duskward and either southward or slightly northward, as predicted under duskward and southward interplanetary magnetic field (IMF). The Cooling model also predicted a significant dawnward propagation of northward‐moving FTEs. Near the MMS footprint, a series of poleward‐moving auroral forms (PMAFs) occurred almost simultaneously with those FTEs. They propagated poleward and westward, consistent with the modeled FTE propagation. The intervals between FTEs, relatively consistent with those between PMAFs, strongly suggest a one‐to‐one correspondence between the dayside transients and ionospheric responses. The FTEs embedded in continuous reconnection observed by MMS and corresponding PMAFs individually occurred during persistent auroral activity recorded by an all‐sky imager strongly indicate that those FTEs/PMAFs resulted from the temporal modulation of the reconnection rate during continuous reconnection. With the decay of the PMAFs associated with the FTEs, patch‐like plasma density enhancements were detected to form and propagate poleward and then dawnward. Propagation to the dawn was also suggested by the Super Dual Auroral Radar Network (SuperDARN) convection and Global Positioning System (GPS) total electron content data. We relate the temporal variation of the driving solar‐wind and magnetospheric mechanism to that of the high‐latitude and polar ionospheric responses and estimate the response time. Plain Language Summary: The solar wind‐magnetosphere coupling often occurs in a nonsteady manner. Such disturbances modify the magnetosphere‐ionosphere system. One of the most common/important processes of such nonsteady phenomena is time‐dependent dayside reconnection, as observationally evidenced by flux transfer events (FTEs), which have been, in turn, represented by ionospheric poleward‐moving auroral forms (PMAFs). Decaying PMAFs have, then, been followed by the occurrence of polar cap patches, which are regions of plasma density enhancements observed in the polar cap. This study indicates a sequence of dynamic processes from the driving solar wind, nonsteady reconnection/FTEs, PMAFs, and polar cap patches. Although a portion of this link has been studied and reported, the complete sequence of these connections and full picture of the solar wind‐magnetopause‐ionosphere coupling have rarely been reported and examined. The series of FTEs embedded in continuous reconnection and corresponding PMAFs individually occurred during persistent auroral activity strongly indicate that the FTEs and PMAFs were in response to the temporal modulation of the reconnection rate during continuous reconnection, rather than the repeated, complete turn‐on and turnoff of dayside reconnection. Our study advances the knowledge of Magnetosphere‐Ionosphere‐Coupling near the cusp region and in the open field‐line region that has been less developed than on closed field lines. Key Points: Multiple flux transfer events (FTEs) were observed to form on the dayside magnetopause under southward and duskward IMFGround‐based observations indicate the poleward‐moving plasma streams or auroral forms (PMAFs) associated with the FTEsDevelopment and transpolar motion of polar cap patches following the PMAFs complete the link of solar wind‐magnetosphere‐ionosphere coupling [ABSTRACT FROM AUTHOR]

On 5 May 2017, MMS observed a crater‐type flux rope on the dawnside tailward magnetopause with fluctuations. The boundary‐normal analysis shows that the fluctuations can be attributed to nonlinear Kelvin‐Helmholtz (KH) waves. Reconnection signatures such as flow reversals and Joule dissipation were identified at the leading and trailing edges of the flux rope. In particular, strong northward electron jets observed at the trailing edge indicated midlatitude reconnection associated with the 3‐D structure of the KH vortex. The scale size of the flux rope, together with reconnection signatures, strongly supports the interpretation that the flux rope was generated locally by KH vortex‐induced reconnection. The center of the flux rope also displayed signatures of guide‐field reconnection (out‐of‐plane electron jets, parallel electron heating, and Joule dissipation). These signatures indicate that an interface between two interlinked flux tubes was undergoing interaction, causing a local magnetic depression, resulting in an M‐shaped crater flux rope, as supported by reconstruction. Plain Language Summary: Magnetic reconnection and Kelvin‐Helmholtz instability (KHI), two of the most fundamental physical processes occurring within the heliosphere and throughout the Universe, often occur simultaneously on the Earth's magnetopause. Previous studies indicate the importance of nonlinearly developed KH waves, which produce multiple kinetic layers facilitating reconnection both in and out of the velocity shear plane and resulting in the magnetic flux rope. However, these studies significantly lacked detailed in situ observations in quantity as well as appropriate 3‐D analyses of the structure of the KH vortex‐induced flux rope. In this paper, we use detailed observations by the MMS spacecraft to investigate both 2‐D and 3‐D structures of the flux rope developed along the KH waves. We found that two flux tubes interact through reconnection to form a single combined structure, which can explain the occurrence of M‐shaped crater flux rope. Key Points: MMS observed a magnetic flux rope formed on the boundary of a nonlinear Kelvin‐Helmholtz (KH) waveBoth in‐plane and midlatitude reconnection associated with the 3‐D structure of the KH vortex‐inducedflux rope were identifiedA current sheet at the flux rope center supported by reconstruction indicates two flux tubes interlinked to form a crater‐type flux rope [ABSTRACT FROM AUTHOR]

Viscous elongation of glass rods has been investigated to improve procedures for producing parabolic capillaries from straight capillaries for use as intensity concentrating x-ray optical elements. Experiments and simulations have been carried out pulling Corning 7740 borosilicate glass rods in a cylindrical furnace. Simulations were based on one-dimensional and two-dimensional finite difference/element calculations, assuming that deformation occurred by linear viscous flow and that the temperatures in the glass remained in equilibrium with the temperatures measured along the axis of the furnace. Rates of elongation in experiments were smaller than those in simulations for later stages of the elongation process. Further experimental and analytical investigations ruled out explanations based on increased viscosities caused by structural relaxation or by partial crystallization and showed that the simulations gave incorrect results because they did not incorporate the dependence of local heat transfer processes on the glass rod radius. [ABSTRACT FROM AUTHOR]

A noncoplanar mesh design that enables electronic systems to achieve large, reversible levels stretchability (>100%) is studied theoretically and experimentally. The design uses semiconductor device islands and buckled thin interconnects on elastometric substrates. A mechanics model is established to understand the underlying physics and to guide the design of such systems. The predicted buckle amplitude agrees well with experiments within 5.5% error without any parameter fitting. The results also give the maximum strains in the interconnects and the islands, as well as the overall system stretchability and compressibility. [ABSTRACT FROM AUTHOR]

In this paper, the particle acceleration processes around magnetotail dipolarization fronts (DFs) were reviewed. We summarize the spacecraft observations (including Cluster, THEMIS, MMS) and numerical simulations (including MHD, test-particle, hybrid, LSK, PIC) of these processes. Specifically, we (1) introduce the properties of DFs at MHD scale, ion scale, and electron scale, (2) review the properties of suprathermal electrons with particular focus on the pitch-angle distributions, (3) define the particle-acceleration process and distinguish it from the particle-heating process, (4) identify the particle-acceleration process from spacecraft measurements of energy fluxes, and (5) quantify the acceleration efficiency and compare it with other processes in the magnetosphere (e.g., magnetic reconnection and radiation-belt acceleration processes). We focus on both the acceleration of electrons and ions (including light ions and heavy ions). Regarding electron acceleration, we introduce Fermi, betatron, and non-adiabatic acceleration mechanisms; regarding ion acceleration, we present Fermi, betatron, reflection, resonance, and non-adiabatic acceleration mechanisms. We also discuss the unsolved problems and open questions relevant to this topic, and suggest directions for future studies. [ABSTRACT FROM AUTHOR]

Spin-orbit coupling (SOC), the interaction between the electron spin and the orbital angular momentum, can unlock rich phenomena at interfaces, in particular interconverting spin and charge currents. Conventional heavy metals have been extensively explored due to their strong SOC of conduction electrons. However, spin-orbit effects in classes of materials such as epitaxial 5d-electron transition-metal complex oxides, which also host strong SOC, remain largely unreported. In addition to strong SOC, these complex oxides can also provide the additional tuning knob of epitaxy to control the electronic structure and the engineering of spin-to-charge conversion by crystalline symmetry. Here, we demonstrate room-temperature generation of spin-orbit torque on a ferromagnet with extremely high efficiency via the spin-Hall effect in epitaxial metastable perovskite SrIrO3.We first predict a large intrinsic spin-Hall conductivity in orthorhombic bulk SrIrO3 arising from the Berry curvature in the electronic band structure. By manipulating the intricate interplay between SOC and crystalline symmetry, we control the spin-Hall torque ratio by engineering the tilt of the corner-sharing oxygen octahedra in perovskite SrIrO3 through epitaxial strain. This allows the presence of an anisotropic spin-Hall effect due to a characteristic structural anisotropy in SrIrO3 with orthorhombic symmetry. Our experimental findings demonstrate the heteroepitaxial symmetry design approach to engineer spin-orbit effects. We therefore anticipate that these epitaxial 5d transition-metal oxide thin films can be an ideal building block for low-power spintronics. [ABSTRACT FROM AUTHOR]

While vorticity defined as the curl of the velocity has been broadly used in fluid and plasma physics, this quantity has been underutilized in space physics due to low time resolution observations. We report Magnetospheric Multiscale (MMS) observations of enhanced electron vorticity in the vicinity of the electron diffusion region of magnetic reconnection. On 11 July 2017 MMS traversed the magnetotail current sheet, observing tailward‐to‐earthward outflow reversal, current‐carrying electron jets in the direction along the electron meandering motion or out‐of‐plane direction, agyrotropic electron distribution functions, and dissipative signatures. At the edge of the electron jets, the electron vorticity increased with magnitudes greater than the electron gyrofrequency. The out‐of‐plane velocity shear along distance from the current sheet leads to the enhanced vorticity. This, in turn, contributes to the magnetic field perturbations observed by MMS. These observations indicate that electron vorticity can act as a proxy for delineating the electron diffusion region of magnetic reconnection. Plain Language Summary: Magnetic reconnection, causing explosive magnetic energy conversion into particle energy, is one of the most fundamental physical processes occurring both within the heliosphere and throughout the universe. The multiscale kinetic structures associated with reconnection have long been a focus in space plasma physics. We investigated how electron vorticity, a physical quantity widely used in fluid physics, but underutilized in the plasma, in particular, reconnection physics, enables us to delineate multiscale kinetic boundaries of reconnection sites using the unprecedented time resolution data from National Aeronautics and Space Administration's Magnetospheric Multiscale spacecraft. The magnitude of electron vorticity to be compared with the electron gyrofrequency provides a frame‐independent indicator of the electron diffusion region, therefore, greatly advancing our ability to delineate the multiscale reconnection boundaries. This study, directly relevant to plasma/reconnection physics, will improve our understanding of fundamental physics with far‐reaching implications in astrophysics. Key Points: We report MMS observation of enhanced electron vorticity in the reconnection siteThe magnitude of electron vorticity greater than the electron gyrofrequency indicates the electron diffusion region of magnetic reconnectionThe enhanced electron vorticity contributes to magnetic field perturbations observed by MMS [ABSTRACT FROM AUTHOR]

Reports a surface passivation study using passivated diodes on Schottky-barrier diodes formed by gold and aluminum contacts. Information on the reverse leakage current barrier height of the passivated diodes; Examination of various approaches to reduce surface state density.

Using data from the MMS mission and the First‐Order Taylor Expansion (FOTE) method, here we reveal electron distribution functions around a reconnection X‐line at the Earth's magnetopause. We find cigar distribution of electrons in both the magnetosphere‐side and magnetosheath‐side inflow regions, isotropic distribution of electrons at the separatrix, and loss of high‐energy electrons in the antiparallel direction in the magnetosheath‐side inflow region. We interpret the formation of cigar distribution in the inflow regions using the Fermi mechanism—as suggested in previous simulations, the loss of high‐energy electrons in the magnetosheath side using the parallel electric fields—which evacuate electrons to escape the diffusion region along the antiparallel direction, and the isotropic distribution at the separatrix using the pitch angle scattering by whistler waves—which exist frequently at the separatrix. We also find that the electron distribution functions can change rapidly (within 60 ms) from isotropic to cigar as the spacecraft moves slightly away from the separatrix. Plain Language Summary: Magnetic reconnection is a key process responsible for many explosive phenomena in nature such as solar flares and magnetospheric substorms. Up to now, the electron behaviors (particularly electron distribution functions) around the reconnection X‐line have not been well revealed, because the X‐line topology is unavailable in previous study. Using data from the MMS mission and the newly developed FOTE method, here we investigate electron distribution functions around a reconnection X‐line and explain the formation mechanisms of these distributions successfully. Key Points: For the first time, we reveal electron distributions around a reconnection X‐line using the FOTE method, rather than cartoons or simulationsWe find different types of electron distributions around the X‐line, and explain the formation mechanisms of these distributions successfullyWe find a rapid change of electron distribution within 60 ms. Such rapid change can only be revealed by FOTE but not other methods [ABSTRACT FROM AUTHOR]

We present results from the reconstruction of the electron diffusion region of magnetotail reconnection observed by the Magnetospheric Multiscale (MMS) spacecraft on 11 July 2017. In the event, the conditions were suited for the reconstruction technique, developed by Sonnerup et al. (2016, https://doi.org/10.1002/2016JA022430), that produces magnetic field and electron streamline maps based on a two‐dimensional, time‐independent, inertialess form of electron magnetohydrodynamic equation, assuming an approximately symmetric current sheet and negligible guide magnetic field. For such a two‐dimensional and steady structure, the X line orientation can be estimated from a method based on Ampère's law using single‐spacecraft measurements of the magnetic field and electric current density. Our reconstruction results indicate that although the X point was not captured inside its tetrahedron, MMS approached the X point as close as one electron inertial length ~27 km. The opening angle of the recovered separatrix field line, combined with theory, suggests that the dimensionless reconnection rate was 0.17, which is consistent with the measured reconnection electric field 2–4 mV/m. The stagnation point of the reconstructed electron flow is shifted earthward of the X point by ~90 km, one possible interpretation of which is discussed. The energy conversion rate j · E′ in the electron frame tends to be higher near the stagnation point, consistent with earlier observations and simulations, and is not correlated with the amplitude of broadband electrostatic waves observed in the upper‐hybrid frequency range. The latter suggests that the waves did not contribute to energy dissipation in this particular electron diffusion region. Plain Language Summary: Magnetic reconnection is a fundamental plasma process that controls transfer of solar wind energy and mass to planetary magnetospheres and causes explosive energy release associated with solar flares and sudden auroral brightening. National Aeronautics and Space Administration's Magnetospheric Multiscale (MMS) mission, which consists of four identical spacecraft launched in March 2015, aims at elucidating how magnetic reconnection works with unprecedented high temporal and spatial resolution measurements of charged particles and electromagnetic fields in space. MMS has been observing the Earth's magnetotail since May 2017 and encountered the central region of magnetic reconnection, called the electron diffusion region, on 11 July 2017. In this study, we present two‐dimensional images of this region recovered from the MMS electron and magnetic field measurements, showing that the electron flow pattern in the electron diffusion region is not as simple as predicted by theory. The results provide new insights about the reconnection process in the actual space environment. Key Points: Electron MHD reconstruction of a magnetotail reconnection region seen by MMS suggests the dimensionless reconnection rate of 0.17MMS did not capture the X point inside its tetrahedron but was less than one electron inertial length ~27 km away at the closest approachThe recovered electron stagnation point is displaced earthward of the X point by ~90 km, about three times the electron inertial length [ABSTRACT FROM AUTHOR]

We report MMS observations of the ion‐scale flux transfer events (FTEs) that may involve two main X lines and tearing instability between the two X lines. The four spacecraft detected multiple isolated regions with enhanced magnetic field strength and bipolar Bn signatures normal to the nominal magnetopause, indicating FTEs. The currents within the FTEs flow mostly parallel to B, and the magnetic tension force is balanced by the total pressure gradient force. During these events, the plasma bulk flow velocity was directed southward. Detailed analysis of the magnetic and electric field and plasma moments variations suggests that the FTEs were initially embedded within the exhaust region north of an X line but were later located southward/downstream of a subsequent X line. The cross sections of the individual FTEs are in the range of ~2.5–6.8 ion inertial lengths. The observations suggest the formation of multiple secondary FTEs. The presence of an X line in the exhaust region southward of a second X line results from the southward drift of an old X line and the reformation of a new X line. The current layer between the two X lines is unstable to the tearing instability, generating multiple ion‐scale flux‐rope‐type secondary islands. Key Points: MMS observation of ion‐scale flux ropes in the reconnection outflow regionThe initial X line is embedded in the exhaust region downstream of a second X lineFlux transfer events (FTE) are formed between the two X lines due to tearing instability [ABSTRACT FROM AUTHOR]

It has been previously reported that adenovirus 36 (Ad36) infection is associated with obesity in humans and other animals. However, there is no clinically available standard protocol to detect Ad36 DNA. In this study, we developed a method for quantitative and rapid detection of Ad36 DNA. Using a TaqMan probe quantitative polymerase chain reaction (qPCR), we identified that the E3 and E4orf1 regions specifically detect Ad36 DNA, because these regions did not show cross reactivity with other types of adenoviruses. The limit of detection was 379 copy/ml and 384 copy/ml for E3 and E4orf1 regions of Ad36, respectively. The %CV (coefficient of variation) for reproducibility of the assay using adenovirus reference material ranged from 1.07-13.02. After we developed the standard protocol to detect Ad36 DNA, we used mouse as a surrogate model to confirm its clinical applicability. We administered Ad36 to mice via intranasal and oral routes, with intraperitoneal administration as the positive control, to analyze the effect of infection route. Ad36 DNA could be detected in lungs, liver, pancreas, and epididymal fat tissue after intraperitoneal injection, whereas it was found only in lungs after intranasal injection. No Ad36 DNA was detectable in any tested organ after oral injection. This indicates that the main route of infection with Ad36 is intranasal, suggesting that Ad36 is a respiratory virus. The standard protocol for qPCR developed in this study is useful for clinical detection of Ad36 DNA. [ABSTRACT FROM AUTHOR]

Dipolarization front (DF)—a sharp boundary separating hot tenuous plasmas from cold dense plasmas—is a key structure responsible for particle acceleration and energy transport in the magnetotail. How such a structure is formed has been unclear so far. Two possible mechanisms suggested in previous studies are magnetic reconnection and spontaneous formation. Both of them require current sheet thinning as a prerequisite. However, observational evidence of the DF formation associated with current sheet thinning has not been reported. In this study, we present such an observation, showing the DF formation after current sheet thinning. We estimate the half thickness of the current sheet to be ∼1000 km and the rate of current sheet thinning as ∼38 km/s. We find that the DF is likely formed at XGSM ≈ −20 RE. During the current sheet thinning, the plasma becomes cold and dense; during DF formation, many magnetic islands are produced. Although current sheet thinning and DF formation have been individually analyzed in the previous studies, this study, for the first time, links the two transient processes in the magnetotail. [ABSTRACT FROM AUTHOR]

Summary: Sperm RNA is a sensitive monitoring endpoint for male reproductive toxicants, and a potential biomarker to assess male infertility and sperm quality. However, isolation of sperm RNA is a challenging procedure due to the heterogeneous population of cells present in the ejaculate, the low yield of RNA per spermatozoon, and the absence of 18S and 28S ribosomal RNA subunits. The unique biology of spermatozoa has created some uncertainty in the field about RNA isolation methods, indicating the need for rigorous quality control checks to ensure reproducibility of data generated from sperm RNA. Therefore, we developed a reliable and effective protocol for RNA isolation from rat and human spermatozoa that delivers highly purified and intact RNA, verified using RNA‐specific electrophoretic chips and molecular biology approaches such as RT‐PCR and Western blot analysis. The sperm RNA isolation technique was optimized using rat spermatozoa and then adapted to human spermatozoa. Three steps in the sperm isolation procedure, epididymal fluid collection, sperm purification, and spermatozoon RNA extraction, were evaluated and assessed. The sperm RNA extraction methodology consists of collection of rat epididymal fluid with repeated needle punctures of the epididymis, somatic cell elimination using detergent‐based somatic cell lysis buffer (SCLB) and the use of RNA isolation Kit. Rat sperm heads are more resistant to disruption than human spermatozoa, necessitating the addition of mechanical lysis with microbeads and heat in the rat protocol, whereas the human sperm protocol only required lysis buffer. In conclusion, this methodology results in reliable and consistent isolation of high‐quality sperm RNA. Using this technique will aid in translation of data collected from animal models, and reproducibility of clinical assessment of male factor fertility using RNA molecular biomarkers. [ABSTRACT FROM AUTHOR]

Abstract: We identify the electron diffusion region (EDR) of a guide field dayside reconnection site encountered by the Magnetospheric Multiscale (MMS) mission and estimate the terms in generalized Ohm's law that controlled energy conversion near the X‐point. MMS crossed the moderate‐shear (∼130°) magnetopause southward of the exact X‐point. MMS likely entered the magnetopause far from the X‐point, outside the EDR, as the size of the reconnection layer was less than but comparable to the magnetosheath proton gyroradius, and also as anisotropic gyrotropic “outflow” crescent electron distributions were observed. MMS then approached the X‐point, where all four spacecraft simultaneously observed signatures of the EDR, for example, an intense out‐of‐plane electron current, moderate electron agyrotropy, intense electron anisotropy, nonideal electric fields, and nonideal energy conversion. We find that the electric field associated with the nonideal energy conversion is (a) well described by the sum of the electron inertial and pressure divergence terms in generalized Ohms law though (b) the pressure divergence term dominates the inertial term by roughly a factor of 5:1, (c) both the gyrotropic and agyrotropic pressure forces contribute to energy conversion at the X‐point, and (d) both out‐of‐the‐reconnection‐plane gradients (∂/∂M) and in‐plane (∂/∂L,N) in the pressure tensor contribute to energy conversion near the X‐point. This indicates that this EDR had some electron‐scale structure in the out‐of‐plane direction during the time when (and at the location where) the reconnection site was observed. [ABSTRACT FROM AUTHOR]

Abstract: Data from the NASA Magnetospheric Multiscale mission are used to investigate asymmetric magnetic reconnection at the dayside boundary between the Earth's magnetosphere and the solar wind. High‐resolution measurements of plasmas and fields are used to identify highly localized (~15 electron Debye lengths) standing wave structures with large electric field amplitudes (up to 100 mV/m). These wave structures are associated with spatially oscillatory energy conversion, which appears as alternatingly positive and negative values of J · E. For small guide magnetic fields the wave structures occur in the electron stagnation region at the magnetosphere edge of the electron diffusion region. For larger guide fields the structures also occur near the reconnection X‐line. This difference is explained in terms of channels for the out‐of‐plane current (agyrotropic electrons at the stagnation point and guide field‐aligned electrons at the X‐line). [ABSTRACT FROM AUTHOR]

Abstract: Using MMS high‐resolution measurements, we present the first observation of fast electron jet (Ve ~2,000 km/s) at a dipolarization front (DF) in the magnetotail plasma sheet. This jet, with scale comparable to the DF thickness (~ 0.9 di), is primarily in the tangential plane to the DF current sheet and mainly undergoes the E × B drift motion; it contributes significantly to the current system at the DF, including a localized ring‐current that can modify the DF topology. Associated with this fast jet, we observed a persistent normal electric field, strong lower hybrid drift waves, and strong energy conversion at the DF. Such strong energy conversion is primarily attributed to the electron‐jet‐driven current (E ⋅ je ≈ 2 E ⋅ ji), rather than the ion current suggested in previous studies. [ABSTRACT FROM AUTHOR]

A dual-band circularly polarized four-arm Spidron fractal antenna is proposed for Ku-band satellite communication. The dual-band characteristic is realized using two-crossed dipole antennas of different lengths. Each dipole arm includes a Spidron fractal patch to generate circular polarization and a printed meander-line to reduce the size. The proposed antenna is fed by a 50-coaxial cable, and a conducting cavity is utilized to obtain a directional circularly polarized radiation pattern. The experiments demonstrate that the fabricated antenna exhibits −10 dB reflection bandwidths ranging from 10.75 GHz to 12.65 GHz and from 13.33 GHz to more than 15 GHz with a broad 3 dB axial ratio bandwidth covering a frequency range of 10.66–14.46 GHz. The measured peak gains are 8.76 dBic in the lower band and 7.43 dBic in the upper band. [ABSTRACT FROM PUBLISHER]

In this letter, we propose to apply the synthetic aperture radar (SAR) technique to improve the cross-range resolution of a digital elevation model (DEM). During a flight, an airborne platform can construct DEM by measuring its distance to the ground through steering a radar beam. To improve the resolution of DEM to the flight direction, SAR technique can be suggested. Through the phase-matching filter in SAR technique, the resolution of point localization can be improved. The simulation results show that the error between original DEM and simulated DEM decreases by 23% with the SAR technique. The localization of the platform using DEM shows that the position estimation improves by 16%. [ABSTRACT FROM AUTHOR]

Background Non-alcoholic fatty liver disease ( NAFLD) is known to be associated with polycystic ovary syndrome ( PCOS). However, most studies investigated the prevalence of NAFLD in obese PCOS patients. Aim To compare the prevalence of non-obese NAFLD in women with or without PCOS, and to assess an independent association between PCOS and NAFLD in a non-obese Asian cohort. Methods This was a case-control study using a prospective PCOS cohort. After subjects with other potential causes of chronic liver disease were excluded, 275 non-obese women with PCOS and 892 non-obese controls were enrolled. NAFLD was determined by hepatic ultrasonography. Main outcomes were the prevalence of NAFLD on hepatic ultrasonography between non-obese women with or without PCOS, and an independent association between non-obese NAFLD and PCOS. Results Non-obese women with PCOS had a significantly higher prevalence of NAFLD than those without PCOS (5.5% vs. 2.8%, P = 0.027). PCOS was associated with non-obese NAFLD (odds ratio: 2.62, 95% confidence intervals: 1.25-5.48) after adjustment for age and body mass index ( BMI). In women with PCOS, the level of androgenicity represented by free testosterone or free androgen index was associated with NAFLD after adjustment for age, BMI, lipid profile, insulin resistance or glycaemic status. Conclusions Non-obese NAFLD is more prevalent in women with polycystic ovary syndrome than in those without. In non-obese patients with polycystic ovary syndrome, hyperandrogenemia may be an independent risk factor for non-obese NAFLD. [ABSTRACT FROM AUTHOR]

Describes a chemical passivation technique for Schottky barrier height enhancement of n-type In[sub0.53]Ga[sub0.47]As surfaces. Details of experimental procedures; Background on the bias-current voltage characteristics of passivated and unpassivated InGaAs Schottky diodes; Explanation for the increase in barrier height of the Schottky contact.

Objectives Primary restless leg syndrome (RLS) and periodic limb movements in sleep (PLMS) frequently co-exist, obscuring the boundaries between the two conditions. In such instances, a study of secondary cases with focal lesions such as post-stroke RLS and PLMS (psRLS and psPLMS, respectively) can be helpful in identifying characteristics of the individual conditions. Materials and Methods Patients who had suffered strokes and who subsequently developed psRLS or psPLMS were recruited. To determine the overall features of psRLS/PLMS, historical cases were selected from the literature. All cases with either psRLS or psPLMS alone were further analyzed to elucidate the distinctive pathomechanisms of the two conditions. Results Six patients with either psRLS or psPLMS were recruited from our hospital; two patients had both conditions contemporaneously. The literature contains details on 30 cases of psRLS or psPLMS. The causative lesion was most frequently located in the pons. We found that psRLS was more often bilateral, and usually detected later in time. Lesions in both the pontine base and tegmentum (together) were associated with unilateral psPLMS, whereas lesions in the corona radiata and adjacent basal ganglia were associated with bilateral RLS. Lesions confined to the corona radiata resulted in either unilateral or bilateral RLS. Conclusions The observed differences in the clinical and radiological features of psRLS and psPLMS suggest that the pathophysiologies of the two conditions are distinct. Further research is needed to understand the pathophysiologies of primary RLS and PLMS. [ABSTRACT FROM AUTHOR]