Ubiquitous solar jets or jet-like activities are generally regarded as an important source of energy and mass input to the upper solar atmosphere and the solar wind. However, their triggering and ...driving mechanisms are not completely understood. By taking advantage of stereoscopic observations with high temporal and spatial resolutions taken by the Solar Dynamic Observatory (SDO) and the Solar Terrestrial Relations Observatory (STEREO), we report an intriguing two-sided-loop jet that occurred on 2013 June 02, and was dynamically associated with the eruption of a mini-filament below an overlying large filament. Additionally, two distinct reconnection processes are identified during the formation stage. The SDO observations reveal that the two-sided-loop jet showed a concave shape with a projection speed of about 80-136 km s−1. From the other view angle, the STEREO observations clearly showed that the trajectories of the two arms of the two-sided-loop were along the cavity magnetic field lines hosting the large filament. Contrary to the well-accepted theoretical model, the present observation sheds new light on our understanding of the formation mechanism of two-sided-loop jets. Moreover, the eruption of the two-sided-loop jet not only supplied mass to the overlying large filament, but also provided a rare opportunity to diagnose the magnetic structure of the overlying large filament via the method of three-dimensional reconstruction.
In recent years, many large‐scale liquefied natural gas (LNG) storage tanks have been built all over the world. Due to their high constructional cost and important functions to the public, the ...academic and engineering communities are very concerned with the operational safety of these important infrastructures once subjected to potentially disastrous actions, that is, earthquakes, typhoons, tsunamis, and so forth. This work presented a benchmark test in evaluating the aseismic performance of extra‐large prestressed reinforced concrete (RC) LNG storage tanks. A 1:14 scaled model of the prototype LNG tank was designed and constructed for shaking table tests. Two recorded and two artificial earthquake ground motions with peak ground acceleration (PGA) up to 1.2g were selected successively as seismic inputs to the tank. The acceleration, displacement, shear force, and strain responses of the model structure were presented, analyzed, and discussed in detail. It was found that due to the differences in the frequency spectra, the seismic excitations have distinct influences on the responses of the tank model. In particular, the wall‐roof junction was detected as the weakest part of the outer tank, and the filling water had non‐negligible effects on the overall seismic responses of the tank. Verified finite element simulations were also presented as supplements to the experimental study. Some suggestions were made with the aim to improve the designs of LNG storage tanks.
Abstract
Investigation of the properties of photospheric magnetic fields could shed light on the generation mechanism of small-scale magnetic fields in quiet regions. In this work, we studied the ...transversal magnetic fields by analyzing the linear polarization (LP) features with Sunrise IMaX data. We calculated the area coverage of LP features, and found that they are 16.1%, 8.6%, and 3% for signals above 3, 3.5, and 4.5 times of noise level, respectively. Those LP features extracted above 4.5 times of noise level are further analyzed. A proper value of 1.5 × 10
15
Mx for the net magnetic flux contained in LP features is selected to divide the LP features into two types (I and II). Among all detected snapshot LP features, 86% of them are in type I and the rest are in type II. The length scales of LP features in these two types follow Gauss and power-law distributions, separately. For the topology of magnetic fields in type I, the magnetic flux patches might be footpoints of flux loops that root inside transversal magnetic fields with one unipolar thick leg or one thick leg together with one thin leg in opposite polarity. For those in type II, about 50% of them contain bipolar magnetic flux patches, but the rest appear without magnetic flux patches.
Variable number tandem repeats (VNTRs) account for significant genetic variation in many organisms. In humans, VNTRs have been implicated in both Mendelian and complex disorders, but are largely ...ignored by genomic pipelines due to the complexity of genotyping and the computational expense. We describe adVNTR-NN, a method that uses shallow neural networks to genotype a VNTR in 18 seconds on 55X whole genome data, while maintaining high accuracy. We use adVNTR-NN to genotype 10,264 VNTRs in 652 GTEx individuals. Associating VNTR length with gene expression in 46 tissues, we identify 163 "eVNTRs". Of the 22 eVNTRs in blood where independent data is available, 21 (95%) are replicated in terms of significance and direction of association. 49% of the eVNTR loci show a strong and likely causal impact on the expression of genes and 80% have maximum effect size at least 0.3. The impacted genes are involved in diseases including Alzheimer's, obesity and familial cancers, highlighting the importance of VNTRs for understanding the genetic basis of complex diseases.
A guest-induced reversible crystal-structure transformation is identified in a new 3D covalent organic framework (COF) by comprehensive analyses using powder X-ray diffraction, organic vapor sorption ...isotherm, and 129Xe NMR spectroscopy. The revolving imine bond in interpenetrating 3D networks is uncovered as the key to the dynamic behavior, the potential applications of which are illustrated by gas separation and heterogeneous catalysis, thus paving the way to the design of stimuli-responsive and multifunctional COF materials.
One of the main challenges for immune checkpoint blockade antibodies lies in malignancies with limited T-cell responses or immunologically "cold" tumors. Inspired by the capability of fever-like heat ...in inducing an immune-favorable tumor microenvironment, mild photothermal therapy (PTT) is proposed to sensitize tumors to immune checkpoint inhibition and turn "cold" tumors "hot." Here we present a combined all-in-one and all-in-control strategy to realize a local symbiotic mild photothermal-assisted immunotherapy (SMPAI). We load both a near-infrared (NIR) photothermal agent IR820 and a programmed death-ligand 1 antibody (aPD-L1) into a lipid gel depot with a favorable property of thermally reversible gel-to-sol phase transition. Manually controlled NIR irradiation regulates the release of aPD-L1 and, more importantly, increases the recruitment of tumor-infiltrating lymphocytes and boosts T-cell activity against tumors. In vivo antitumor studies on 4T1 and B16F10 models demonstrate that SMPAI is an effective and promising strategy for treating "cold" tumors.
This systematic review and meta-analysis aims to determine the current evidence on risk factors for type II endoleaks after endovascular aneurysm repair (EVAR).
A systematic literature search was ...carried out for studies that evaluated the association of demographic, co-morbidity, and other patient-determined factors with the onset of type II endoleaks. Pooled prevalence of type II endoleaks after EVAR was updated.
Among the 504 studies screened, 45 studies with a total of 36,588 participants were included in this review. The pooled prevalence of type II endoleaks after EVAR was 22% 95% confidence interval (CI), 19%-25%. The main factors consistently associated with type II endoleaks included age pooled odds ratio (OR), 0.37; 95% CI, 0.31-0.43; P<0.001, smoking (pooled OR, 0.71; 95% CI, 0.55-0.92; P<0.001), patent inferior mesenteric artery (pooled OR, 1.98; 95% CI, 1.06-3.71; P = 0.012), maximum aneurysm diameter (pooled OR, 0.23; 95% CI, 0.17-0.30; P<0.001), and number of patent lumbar arteries (pooled OR, 3.07; 95% CI, 2.81-3.33; P<0.001). Sex, diabetes, hypertension, anticoagulants, antiplatelet, hyperlipidemia, chronic renal insufficiency, types of graft material, and chronic obstructive pulmonary diseases (COPD) did not show any association with the onset of type II endoleaks.
Clinicians can use the identified risk factors to detect and manage patients at risk of developing type II endoleaks after EVAR. However, further studies are needed to analyze a number of potential risk factors.
A solar jet that occurred on 2014 July 31, which was accompanied by a GOES C1.3 flare and a mini-filament eruption at the jet base, was studied by using observations taken by the New Vacuum Solar ...Telescope and the Solar Dynamic Observatory. Magnetic field extrapolation revealed that the jet was confined in a fan-spine magnetic system that hosts a null point at the height of about 9 Mm from the solar surface. An inner flare ribbon surrounded by an outer circular ribbon and a remote ribbon were observed to be associated with the eruption, in which the inner and remote ribbons, respectively located at the footprints of the inner and outer spines, while the circular one manifested the footprint of the fan structure. It is worth noting that the west part of the circular ribbon exhibited an interesting round-trip slipping motion, while the inner ribbon and the circular ribbon's east part displayed a northward slipping motion. Our analysis results indicate that the slipping motions of the inner and the circular flare ribbons reflected the slipping magnetic reconnection process in the fan's quasi-separatrix layer, while the remote ribbon was associated with the magnetic reconnection at the null point. In addition, the filament eruption was probably triggered by the magnetic cancellation around its south end, which further drove the slipping reconnection in the fan quasi-separatrix layer and the reconnection at the null point.
Abstract
The phenomenon of peripheral coronal loop contraction during solar flares and eruptions, recently discovered in observations, has gradually drawn the attention of solar physicists. However, ...its underlying physical mechanism is still uncertain. One possible mechanism is Hudson’s implosion conjecture, which attributes the contraction of peripheral coronal loops to magnetic pressure reduction in the magnetic energy liberation core, while other researchers proposed alternative explanations. In previous observational studies we also note the disappearance of peripheral shrinking loops in the late phase, of which there is a lack of investigation and interpretation. In this paper, we exploit a full MHD simulation of solar eruption to study the causes of the two phenomena. It is found that the loop motion in the periphery is well correlated with magnetic energy accumulation and dissipation in the core, and the loop shrinkage is caused by a more significant reduction in magnetic pressure gradient force than in magnetic tension force, consistent with the implosion conjecture. The peripheral contracting loops in the late phase act as inflow to reconnect with central erupting structures, which destroys their identities and naturally explains their disappearance. We also propose a positive feedback between the peripheral magnetic reconnection and the central eruption.
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