The Magnetospheric Multiscale (MMS) mission was designed to make observations in the very small electron diffusion region (EDR), where magnetic reconnection takes place. From a data set of over 4500 ...magnetopause crossings obtained in the first phase of the mission, MMS had encounters near or within 12 EDRs. These 12 events and associated magnetopause crossings are considered as a group to determine if they span the widest possible range of external and internal conditions (i.e., in the solar wind and magnetosphere). In addition, observations from MMS are used to determine if there are multiple X‐lines present and also to provide information on X‐line location relative to the spacecraft. These 12 events represent nearly the widest possible range of conditions at the dayside magnetopause. They occur over a wide range of local times and magnetic shear angles between the magnetosheath and magnetospheric magnetic fields. Most show evidence for multiple reconnection sites.
Key Points
MMS X‐line events cover a wide range of external conditions
Almost all X‐line events are associated with multiple X‐lines at the magnetopause
Reconnection between the magnetosheath and an existing boundary layer is required for KH instability
To explore the characteristics of Helicobacter pylori resistance in China and the association between antibiotic resistance and several clinical factors.
H. pylori strains were collected from ...patients in 13 provinces or cities in China between 2010 and 2016. Demographic data including type of disease, geographic area, age, gender and isolation year were collected to analyse their association with antibiotic resistance. Antibiotic resistance was detected using the Etest test and the Kirby-Bauer disc diffusion method.
H. pylori were successfully cultured from 1117 patients. The prevalence of metronidazole, clarithromycin (CLA), azithromycin, levofloxacin (LEV), moxifloxacin, amoxicillin (AMO), tetracycline and rifampicin resistance was 78.2, 22.1, 23.3, 19.2, 17.2, 3.4, 1.9 and 1.5%, respectively. No resistance to furazolidone was observed. The resistance rates to LEV and moxifloxacin were higher in strains isolated from patients with gastritis compared to those with duodenal ulcer and among women. Compared to patients ≥40 years old, younger patients exhibited lower resistance rates to CLA, azithromycin, LEV and moxifloxacin. The resistance rates to CLA and AMO were higher in strains isolated more recently, and we also found that the prevalence of resistance to metronidazole, CLA, azithromycin and AMO were significantly different among different regions of China.
The resistance rates to metronidazole, CLA and LEV were high in China. Patient age, gender, disease and location were associated with the resistance of H. pylori to some antibiotics. Furazolidone, AMO and tetracycline are better choices for H. pylori treatment in China.
Electron heating and mixing during asymmetric reconnection are studied with a 3‐D kinetic simulation that matches plasma parameters from Magnetospheric Multiscale (MMS) spacecraft observations of a ...magnetopause diffusion region. The mixing and heating are strongly enhanced across the magnetospheric separatrix compared to a 2‐D simulation. The transport of particles across the separatrix in 3‐D is attributed to lower hybrid drift turbulence excited at the steep density gradient near the magnetopause. In the 3‐D simulation (and not the 2‐D simulation), the electron temperature parallel to the magnetic field within the mixing layer is significantly higher than its upstream value in agreement with the MMS observations.
Key Points
A fully kinetic 3‐D simulation resolves electron mixing and heating at a magnetopause reconnection site matching MMS observations
Lower hybrid range drift turbulence mixes plasma across the magnetospheric separatrix
Strong parallel electron heating near the current layer, as observed by MMS, is reproduced only in 3‐D
Kabuki or Niikawa–Kuroki syndrome (KS) is a rare disorder with multiple malformations and recurrent infections, especially otitis media. This study aimed to investigate the genetic defects in Kabuki ...syndrome and determine if immune status is related to recurrent otitis media. Fourteen patients from 12 unrelated families were enrolled in the 9‐year study period (2005–2013). All had Kabuki faces, cleft palate, developmental delay, mental retardation, and the short fifth finger. Recurrent otitis media (12/14) and hearing impairment (8/14) were also more common features. Immunologic analysis revealed lower memory CD19+ cells (11/13), lower memory CD4+ cells (8/13), undetectable anti‐HBs antibodies (7/13), and antibody deficiency (7/13), including lower IgA (4), IgG (2), and IgG2 (1). Naïve emigrant lymphocytes, lymphocyte proliferation function, complement activity, and superoxide production in polymorphonuclear cells were all normal. All the patients had KMT2D mutations and 10 novel mutations of R1252X, R1757X,Y1998C, P2550R fs2604X, Q4013X, G5379X, E5425K, R5432X, R5432W, and R5500W. Resembling the phenotype of common variable immunodeficiency, KS patients with antibody deficiency, decreased memory cells, and poor vaccine response increased susceptibility to recurrent otitis media. Large‐scale prospective studies are warranted to determine if regular immunoglobulin supplementation decreases the frequency of otitis media and severity of hearing impairment.
Dysbiotic oral microbiota has been associated with multiple sclerosis. However, the role and mechanism of oral microbiota in the development of multiple sclerosis are still elusive. Here, we ...demonstrated that ligature-induced periodontitis (LIP) aggravated experimental autoimmune encephalomyelitis (EAE) in mice, and this was likely dependent on the expansion of T helper 17 (Th17) cells. LIP increased the splenic richness of Enterobacter sp., which was able to induce the expansion of splenic Th17 cells and aggravate EAE in mice. LIP also led to enrichment of Erysipelotrichaceae sp. in the gut and increased Th17 cells in the large intestinal lamina propria of EAE mice. Fecal microbiota transplantation from EAE mice with LIP also promoted EAE symptoms. In conclusion, periodontitis exacerbates EAE, likely through ectopic colonization of oral pathobionts and expansion of Th17 cells.
The molecular characterization of cytogenetic abnormalities has not only provided insights into the mechanisms of leukemogenesis but also led to the establishment of new treatment strategies ...targeting these abnormalities and thereby further improve the prognosis of patients. We analyzed the prognosis of 1091 Chinese patients with newly diagnosed acute lymphoblastic leukemia (ALL) and explored the prognostic impacts of a large number of cytogenetic/molecular abnormalities. It was demonstrated that, in both B- and T-ALL settings, the prognosis was negatively correlated to the age as reported to date. For childhood T-ALL patients, it was also documented that the HOX11 expression represented a favorable prognostic factor as it was in adult ones. We identified CRLF2 overexpression as an intermediate-risk marker and Ik6 variant of IKZF1 gene as a high-risk one when stratifying pediatric B-ALL cases according to cytogenetic/molecular risks. We also found that Ik6 variant and CRLF2 overexpression had an important role in dictating the prognosis of Ph-negative patients, which may be useful markers in guiding the treatment of ALL in the future, with tyrosine kinase inhibitors on the other hand reversing the fate of Ph-positive ALL patients.
We study electron distribution functions in a diffusion region of antiparallel asymmetric reconnection by means of particle-in-cell simulations and analytical theory. At the electron stagnation ...point, the electron distribution comprises a crescent-shaped population and a core component. The crescent-shaped distribution is due to electrons coming from the magnetosheath toward the stagnation point and accelerated mainly by electric field normal to the current sheet. Only a part of magnetosheath electrons can reach the stagnation point and form the crescent-shaped distribution that has a boundary of a parabolic curve. The penetration length of magnetosheath electrons into the magnetosphere is derived. We expect that satellite observations can detect crescent-shaped electron distributions during magnetopause reconnection.
We perform an observationally based evaluation of the cloud ice water content (CIWC) and path (CIWP) of present‐day GCMs, notably 20th century CMIP5 simulations, and compare these results to CMIP3 ...and two recent reanalyses. We use three different CloudSat + CALIPSO ice water products and two methods to remove the contribution from the convective core ice mass and/or precipitating cloud hydrometeors with variable sizes and falling speeds so that a robust observational estimate can be obtained for model evaluations. The results show that for annual mean CIWP, there are factors of 2–10 in the differences between observations and models for a majority of the GCMs and for a number of regions. However, there are a number of CMIP5 models, including CNRM‐CM5, MRI, CCSM4 and CanESM2, as well as the UCLA CGCM, that perform well compared to our past evaluations. Systematic biases in CIWC vertical structure occur below the mid‐troposphere where the models overestimate CIWC, with this bias arising mostly from the extratropics. The tropics are marked by model differences in the level of maximum CIWC (∼250–550 hPa). Based on a number of metrics, the ensemble behavior of CMIP5 has improved considerably relative to CMIP3, although neither the CMIP5 ensemble mean nor any individual model performs particularly well, and there are still a number of models that exhibit very large biases despite the availability of relevant observations. The implications of these results on model representations of the Earth radiation balance are discussed, along with caveats and uncertainties associated with the observational estimates, model and observation representations of the precipitating and cloudy ice components, relevant physical processes and parameterizations.
Key Points
A robust evaluation of the cloud ice water content for GCMs
Implications of this study on model representations of the Earth radiation
Magnetic reconnection in a quasi‐parallel bow shock is investigated with two‐dimensional local particle‐in‐cell simulations. In the shock transition and downstream regions, large amplitude magnetic ...fluctuations exist, and abundant current sheets form. In some current sheets, reconnection occurs, and ion‐scale and electron‐scale magnetic islands are generated. In electron‐scale island regions, only electron outflow jets are observed, producing a quadrupolar out‐of‐plane magnetic field pattern, while in ion‐scale islands, both ions and electrons are involved and energized in reconnection. Normalized reconnection rates are obtained to be between around 0.1 to 0.2, and particle acceleration signatures are seen in distribution functions.
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