Stereo methods using GOES‐17 and Himawari‐8 applied to the Hunga Tonga‐Hunga Ha'apai volcanic plume on 15 January 2022 show overshooting tops reaching 50–55 km altitude, a record in the satellite ...era. Plume height is important to understand dispersal and transport in the stratosphere and climate impacts. Stereo methods, using geostationary satellite pairs, offer the ability to accurately capture the evolution of plume top morphology quasi‐continuously over long periods. Manual photogrammetry estimates plume height during the most dynamic early phase of the eruption and a fully automated algorithm retrieves both plume height and advection every 10 min during a more frequently sampled and stable phase beginning 3 hr after the eruption. Stereo heights are confirmed with Global Navigation Satellite System Radio Occultation bending angles, showing that much of the plume was lofted 30–40 km into the atmosphere. Cold bubbles are observed in the stratosphere with brightness temperature of ∼173 K.
Plain Language Summary
The Hunga Tonga‐Hunga Ha'apai volcano in the South Pacific erupted violently on 15 January 2022. A volcanic plume from the eruption was lofted into the stratosphere to altitudes that are unprecedented in the era of satellite observations. We observed the highest part of the plume at 55 km and tracked the motion of the plume in 3D in the vicinity of the volcano for a 7‐hr period, every 10 min, using imagery from the geostationary GOES‐17 and Himawari‐8 satellites that are positioned at different locations on the equator. The apparent shift in the plume as seen from two different vantage points contains information about the plume height and the apparent movement of the plume as it is repeatedly observed by one satellite contains information about the plume velocity. We confirmed our height observations using radio occultation measurements that NOAA uses to profile the atmosphere. Radio waves are normally bent as they pass through the atmosphere from satellite to satellite, nearly grazing the Earth's surface, but when radio waves pass through the volcanic plume, there is an anomalously large change in bending angle.
Key Points
The Hunga Tonga‐Hunga Ha'apai eruption of 15 January 2022, lofted material above 30 km to record‐breaking heights of ∼55 km
Our stereo‐winds code retrieved height and motion vectors from GOES‐17 and Himawari‐8 every 10 min shortly after the eruption
Radio occultation bending angles confirm plume altitudes
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
In this article, we introduce an inertial projection and contraction algorithm by combining inertial type algorithms with the projection and contraction algorithm for solving a variational inequality ...in a Hilbert space
H
. In addition, we propose a modified version of our algorithm to find a common element of the set of solutions of a variational inequality and the set of fixed points of a nonexpansive mapping in
H
. We establish weak convergence theorems for both proposed algorithms. Finally, we give the numerical experiments to show the efficiency and advantage of the inertial projection and contraction algorithm.
Tungsten copper (W-Cu) composites, as a traditional refractory material, are promising materials for manufacture of electrical contacts and electrodes, heavy duty electronic contacts, welding and ...electro-forging dies, heat sinks, packaging material, arcing resistance electrodes and thermal management devices owing to their excellent properties. This critical review presents and discusses the current progress of W-Cu composites. Starting with an introduction of the synthesis methods for W-Cu composites, including the conventional and modern preparation approaches. After that we focus on the description of the improvement of mechanical properties and arc-erosion properties by modification techniques. Finally, the advantages of W-Cu composites in applications such as electrical contacts, electronic packaging materials, and heat sinks, as well as military materials, are described, respectively.
•W-Cu composites have been developed and widely used over a wide range.•This critical review presents and discusses the current progress of W-Cu composites.•Graphene is a promising reinforcement phase for W-Cu composites in the further.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The current therapies to treat hepatitis B virus (HBV) infection are limited. Recently, clustered regularly interspaced short palindromic repeat (CRISPR) systems, originally identified in bacteria ...and archaea, have been found to consist of an RNA-based adaptive immune system that degrades complimentary sequences of invading plasmids and viruses. Here, we studied the effects of the CRISPR/CRISPR-associated Cas9 system that was targeted to the surface antigen (HBsAg)-encoding region of HBV, both in a cell culture system and in vivo. The HBsAg levels in the media of the cells and in the sera of mice were analyzed by a quantitative enzyme-linked immunosorbent assay. The HBV DNA levels were assessed by quantitative PCR and HBsAg expression in mouse livers was assessed by an immunohistochemical assay. The amount of HBsAg secreted in the cell culture and mouse serum was reduced by CRISPR/Cas9 treatment. Immunohistochemistry analyses showed almost no HBsAg-positive cells in the liver tissue of CRISPR/Cas9-S1+X3-treated mice. The CRISPR/Cas9 system efficiently produced mutations in HBV DNA. Thus, CRISPR/Cas9 inhibits HBV replication and expression in vitro and in vivo and may constitute a new therapeutic strategy for HBV infection.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
To investigate the risk factors associated with the development of thrombocytopenia, and define the thresholds of efficacy and safety in critically ill patients who received linezolid therapy. A ...retrospective study was performed in critically ill patients treated with linezolid. Risk factors associated with thrombocytopenia were identified via medical records and trough levels (C
min
) measured during linezolid treatment. By establishing a logistic model, the risks were predicted by the receiver operating characteristic (ROC) curve and the thresholds of efficacy and safety were identified in the patients. Logistic analysis showed that, weight (OR = 0.906; 95 % CI, 0.839–0.978;
P
= 0.011), baseline platelet count (OR = 0.989; 95 % CI, 0.977–1.000;
P
= 0.049), C
min
(OR = 1.545; 95 % CI, 1.203–1.983;
P
= 0.001), and APACHE II score (OR = 1.130; 95 % CI, 1.003–1.273;
P
= 0.044) were significant factors for linezolid-associated thrombocytopenia. The area under the ROC curve of the combined predictor was larger based on the above factors. When the Youden index was the maximum, the best optimal cut-off point was 205.6 on the ROC curve; when C
min
≥ 2 mg/L, the probability of bacterial eradication was more than 80 %; when C
min
≥ 6.3 mg/L, the probability of thrombocytopenia was more than 50 %. In clinical practice, when the calculating results of the combined predictor ≤205.6, the risk of the development of thrombocytopenia may be higher. Furthermore, maintenance of C
min
between 2 and 6.3 mg/L over time may be helpful in retaining appropriate efficacy and reducing the associated thrombocytopenia.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The jamming is found to increase significantly in recent years, and its impact is evident in Global Navigation Satellite System (GNSS) radio occultation (RO) measurements, such as those from ...COSMIC-2. This article presents an algorithm that applies the RO radiometry to detect and monitor long-term variations of GNSS jamming power from a deeply occulted height (H SL = −140 km). At these heights, the RO signal amplitude is at its noise level because the GNSS transmitter is far behind the Earth shadow. Thus, any enhanced RO amplitudes from these heights are considered as a jamming signal. The algorithm was successfully applied to two conflict zones: Mediterranean Sea and Middle East and Central Africa, where the Global Position System (GPS) jamming was frequently used by state-sponsored electronic warfare. The time series of normalized RO amplitude in these regions show a steady increase of the GPS jamming power since 2017, but a sharp decrease since the start of Russo-Ukrainian War.
Ionospheric scintillation can significantly degrade the performance and the usability of
space‐based communication and navigation signals. Characterization and prediction of ionospheric
scintillation ...can be made from the Global Navigation Satellite System (GNSS) radio occultation (RO)
technique using the measurement from a deep slant path where the RO tangent height (ht) is far
below the ionospheric sources. In this study, the L–band S4 from the RO measurements at ht = 30
km is used to infer the amplitude scintillation on the ground. The analysis of global RO data at ht =
30 km shows that sporadic–E (Es), equatorial plasma bubbles (EPBs), and equatorial spread–F (ESF)
produce most of the significant S4 enhancements, although the polar S4 is generally weak. The
enhanced S4 is a strong function of local time and magnetic dip angle. The Es–induced daytime S4
tends to have a negative correlation with the solar cycle at low latitudes but a positive correlation at
high latitudes. The nighttime S4 is dominated by a strong semiannual variation at low latitudes.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Scattering differences induced by frozen particle microphysical properties are investigated, using the vertically (V) and horizontally (H) polarized radiances from the Global Precipitation ...Measurement (GPM) Microwave Imager (GMI) 89 and 166 GHz channels. It is the first study on frozen particle microphysical properties on a global scale that uses the dual-frequency microwave polarimetric signals. From the ice cloud scenes identified by the 183.3±3 GHz channel brightness temperature (TB), we find that the scattering by frozen particles is highly polarized with V-H polarimetric differences (PD) being positive throughout the tropics and the winter hemisphere mid-latitude jet regions, including PDs from the GMI 89 and 166 GHz TBs, as well as the PD at 640 GHz from the ER-2 Compact Scanning Submillimeter-wave Imaging Radiometer (CoSSIR) during the TC4 campaign. Large polarization dominantly occurs mostly near convective outflow region (i.e., anvils or stratiform precipitation), while the polarization signal is small inside deep convective cores as well as at the remote cirrus region. Neglecting the polarimetric signal would easily result in as large as 30% error in ice water path retrievals. There is a universal "bell-curve" in the PD - TB relationship, where the PD amplitude peaks at ~ 10 K for all three channels in the tropics and increases slightly with latitude (2-4 K). Moreover, the 166 GHz PD tends to increase in the case where a melting layer is beneath the frozen particles aloft in the atmosphere, while 89 GHz PD is less sensitive than 166 GHz to the melting layer. This property creates a unique PD feature for the identification of the melting layer and stratiform rain with passive sensors. Horizontally oriented non-spherical frozen particles are thought to produce the observed PD because of different ice scattering properties in the V and H polarizations. On the other hand, turbulent mixing within deep convective cores inevitably promotes the random orientation of these particles, a mechanism works effectively on reducing the PD. The current GMI polarimetric measurements themselves cannot fully disentangle the possible mechanisms.
Objective Under the same power configuration, the cost of a permanent magnet synchronous traction system is higher than that of an asynchronous traction system. However, the former can effectively ...reduce the operational consumption of trains. Therefore, it is necessary to analyze the feasibility of applying permanent magnet traction technology in engineering projects. Method Taking the Nanjing Metro Line 9 as an example, a comparative analysis is conducted on the system configuration, operational energy consumption, and maintenance cost of permanent magnet synchronous traction system and asynchronous traction system. An improvement proposal is presented to change the train power configuration from 4M2T (4 motor 2 trailer) to 3M3T (3 motor 3 trailer), and a comparative analysis of the traction and braking performance of the two power configurations is performed. Result & Conclusion The 3M3T configuration with a permanent magnet synchronous traction system can effectively reduce the operational energy con
Colonization by Lactobacillus in the female genital tract is thought to be critical for maintaining genital health. However, little is known about how genital microbiota influence host immune ...function and modulate disease susceptibility. We studied a cohort of asymptomatic young South African women and found that the majority of participants had genital communities with low Lactobacillus abundance and high ecological diversity. High-diversity communities strongly correlated with genital pro-inflammatory cytokine concentrations in both cross-sectional and longitudinal analyses. Transcriptional profiling suggested that genital antigen-presenting cells sense gram-negative bacterial products in situ via Toll-like receptor 4 signaling, contributing to genital inflammation through activation of the NF-κB signaling pathway and recruitment of lymphocytes by chemokine production. Our study proposes a mechanism by which cervicovaginal microbiota impact genital inflammation and thereby might affect a woman’s reproductive health, including her risk of acquiring HIV.
•Most African women studied had genital communities with low Lactobacillus abundance•Unlike the gut, high-diversity cervicovaginal communities are pro-inflammatory•Specific bacteria induce cytokine production from genital APCs and epithelial cells
Vaginal colonization by a single bacterium, Lactobacillus, is considered healthy. Kwon and colleagues show that in a cohort of asymptomatic African women, the majority have high-diversity genital bacterial communities that are closely associated with local inflammation. This work suggests specific genital bacteria might increase HIV acquisition risk in women.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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