The Heifangtai terrace is located in the arid loess area in northwestern China, where a large number of landslides was induced by agricultural irrigation on the terrace, resulted in slope retreat at ...the terrace edge at an estimated rate of 0.024km2yr−1. On the basis of field investigation and monitoring, remote sensing and aerial images, and laboratory tests, we analyzed the characteristics of slope retreat and the failure mechanism of the loess flowslides. The retreat of slope is caused by the retrogressive behavior of the loess flowslide, of which new failure develops at the backwall of the preceding one. The groundwater level variation governs the failure process and mechanism of the flowslides. The observed loess flowslides were accompanied by rapid slope deformation, high velocity, and long runout distance exhibiting liquefaction and fluidization during the movement. In the event of a loess flowslide, a small-scale drained slope failure produces a concave recession first intensifies localized groundwater flow on the slope surface while the flow is being impeded by the deposit, which produces an undrained condition with increasing localized pore-water pressure, and in turn facilitates the subsequent flowslide. Results of the isotropically consolidated undrained triaxial tests (ICU) and constant shear stress drained triaxial tests (CSD) revealed the strain-softening behavior in the saturated reconstituted loess, and they showed that the excess pore-water pressure is associated with a small axial displacement and possibly facilitated by some alternations in the loess structure at the micro-scale.
•The slope retreat in Heifangtai is largely caused by retrogressive loess flowslide.•Retrogressive failure is related to rising groundwater level due to irrigation.•Long-runout flowslide is associated with strain-softening and static liquefaction.•Retrogressive loess flowslide is likely to recur as surface irrigation continues.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In the fiber communication domain, people are facing the challenges due to the rapidly growing requirement on the capacity from new functions and services. Multi-hump solitons are therefore noticed ...and studied on the feasibility of improving the capacity of the optical fiber communication. In this paper, we study the vector bright solitons and their interaction properties of the coupled Fokas–Lenells system, which models the femtosecond optical pulses in a birefringent optical fiber. We derive the so-called degenerate and nondegenerate vector solitons associated with the one and two eigenvalues, respectively, and the latter admits the symmetric profile. Asymptotically and graphically, interaction patterns of such solitons are classified as follows: Interactions between the degenerate solitons can be elastic or inelastic, reflecting the intensity redistribution between the two components; Interactions between the degenerate and nondegenerate solitons are inelastic, which make the nondegenerate solitons maintaining or losing the profiles in the different situations; Interactions between the nondegenerate solitons do not cause the intensity redistribution, while their shapes change slightly or remain unchanged.
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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
Agricultural irrigation has increased the groundwater level in the Heitai terrace (part of the Heifangtai terrace) by 20m over nearly five decades, which causes 3–5 landslides each year at the edge ...of the terrace. The Heitai terrace is of great interest in the study of loess-related landslides; but there is no unanimous agreement on the types of either the landslides in this study site or the loess-related slope failures in general. On the basis of aerial images (res. 5cm), Digital Elevation Model (res. 10cm), and field investigations, we analyzed the distribution and failure mode of the landslides in Heitai. The geological structure and characteristics of 69 landslides (vol. 5×103–6×106m3) are studied. The preliminary results of groundwater recharge in the terrace and formation of the apparent spring lines on the slope surface are analyzed to better understand the failure modes. We divided the landslides in Heitai into two groups based on the location of the failure surface, i.e. loess landslide and loess-bedrock landslide, of which the development is governed by the angle between the principle direction of slope deformation and the dip of bedrock bedding. We further analyzed the failure mode of each type observed in Heitai, defined as follows: loess-bedrock planar slide, loess-bedrock irregular slide, loess flowslide, loess slide, and loess flow. The proposed types of loess-related landslide are to be incorporated in the Varnes classification (Varnes, 1978) in consideration of the engineering properties of loess, and to provide backward compatibility for Heitai and potentially other regions in the Loess Plateau of China.
•Categorized 69 landslides in Heitai terrace into 2 regions and 7 sections;•Defined loess-bedrock planar slide, loess flowslide, loess slide, and loess flow;•Failure surface development is governed by bedrock dip and sliding direction.•Landslide type and failure mode is affected by groundwater movements.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
RIPK3 amyloid complex plays crucial roles during TNF-induced necroptosis and in response to immune defense in both human and mouse. Here, we have structurally characterized mouse RIPK3 homogeneous ...self-assembly using solid-state NMR, revealing a well-ordered N-shaped amyloid core structure featured with 3 parallel in-register β-sheets. This structure differs from previously published human RIPK1/RIPK3 hetero-amyloid complex structure, which adopted a serpentine fold. Functional studies indicate both RIPK1-RIPK3 binding and RIPK3 amyloid formation are essential but not sufficient for TNF-induced necroptosis. The structural integrity of RIPK3 fibril with three β-strands is necessary for signaling. Molecular dynamics simulations with a mouse RIPK1/RIPK3 model indicate that the hetero-amyloid is less stable when adopting the RIPK3 fibril conformation, suggesting a structural transformation of RIPK3 from RIPK1-RIPK3 binding to RIPK3 amyloid formation. This structural transformation would provide the missing link connecting RIPK1-RIPK3 binding to RIPK3 homo-oligomer formation in the signal transduction.
Broadened antibacterial activity was introduced to rhodanine derivatives targeting Mycobacterial tuberculosis enoyl-acyl carrier protein reductase (Mtb InhA) by recruiting feature of xacins to bring ...DNA Gyrase B inhibitory capability. This is significant for preventing further bacterial injections in the tuberculosis treatment. The most potent compound Cy14 suggested comparable bioactivity (IC50 = 3.18 µM for Mtb InhA; IC50 = 10 nM for DNA Gyrase B) with positive controls. Structure–activity relationship discussion and molecular docking model revealed the significance of rhodanine moiety and derived methoxyl on meta-position, pointing out orientations for future modification.
The release of toxic organic pollutants and heavy metals by primitive electronic waste (e-waste) processing to waterways has raised significant concerns, but little is known about their potential ...ecological effects on aquatic biota especially microorganisms. We characterized the microbial community composition and diversity in sediments sampled along two rivers consistently polluted by e-waste, and explored how community functions may respond to the complex combined pollution. High-throughput 16S rRNA gene sequencing showed that Proteobacteria (particularly Deltaproteobacteria) dominated the sediment microbial assemblages followed by Bacteroidetes, Acidobacteria, Chloroflexi and Firmicutes. PICRUSt metagenome inference provided an initial insight into the metabolic potentials of these e-waste affected communities, speculating that organic pollutants degradation in the sediment might be mainly performed by some of the dominant genera (such as Sulfuricurvum, Thiobacillus and Burkholderia) detected in situ. Statistical analyses revealed that toxic organic compounds contributed more to the observed variations in sediment microbial community structure and predicted functions (24.68% and 8.89%, respectively) than heavy metals (12.18% and 4.68%), and Benzo(a)pyrene, bioavailable lead and electrical conductivity were the key contributors. These results have shed light on the microbial assemblages in e-waste contaminated river sediments, indicating a potential influence of e-waste pollution on the microbial community structure and function in aquatic ecosystems.
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•River sediments from Guiyu were severely polluted by TOPs and heavy metals.•Deltaproteobacteria dominated the sediment microbial assemblages.•Some of the dominant genera might harbor pathways for TOPs degradation.•TOPs contributed more to community structure and function than heavy metals.•BaP, available lead and EC were the key contributors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Non‐small cell lung cancer (NSCLC) accounts for ~85% of all lung cancer cases. Neferine is used as a traditional Chinese medicine with many pharmacological effects, including antitumor properties; ...however, it has not been reported whether neferine plays an anticancer role by causing pyroptosis in NSCLC cells. We used two typical lung cancer cell lines, A549 and H1299, and 42 lung cancer tissue samples to investigate the regulatory effects of neferine on TGF‐β and MST1. We also treated lung cancer cells with different concentrations of neferine to study its effects on lung cancer cell survival, migration, invasion, and epithelial–mesenchymal transition (EMT) as well as on pyroptosis. Lentivirus‐mediated gain‐of‐function studies of TGF‐β and MST1 were applied to validate the roles of TGF‐β and MST1 in lung cancer. Next, we used murine transplanted tumor models to evaluate the effect of neferine treatment on the metastatic capacity of lung cancer tissues. With increasing neferine concentration, the viability, migration, invasion, and EMT capacity of A549 and H1299 cells decreased, whereas pyroptosis increased. Neferine repressed TGF‐β expression to modulate the induction of reactive oxygen species (ROS) by MST1. Overexpression of TGF‐β in either in vitro or mouse‐transplanted A549 cells restored the inhibitory effect of neferine on tumor development. Overexpression of MST1 clearly enhanced pyroptosis. Neferine contributed to pyroptosis by regulating MST1 expression through downregulation of TGF‐β to induce ROS formation. Therefore, our study shows that neferine can serve as an adjuvant therapy for NSCLC patients.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
MicroRNAs (miRNAs) play crucial roles in regulating plant development and stress responses. However, the functions and mechanism of intronic miRNAs in plants are poorly understood. This study reports ...a stress-responsive RNA splicing mechanism for intronic miR400 production, whereby miR400 modulates reactive oxygen species (ROS) accumulation and improves plant tolerance by downregulating its target expression. To monitor the intron splicing events, we used an intronic miR400 splicing-dependent luciferase transgenic line. Luciferase activity was observed to decrease after high cadmium concentration treatment due to the retention of the miR400-containing intron, which inhibited the production of mature miR400. Furthermore, we demonstrated that under Cd treatments, Pentatricopeptide Repeat Protein 1 (PPR1), the target of miR400, acts as a positive regulator by inducing ROS accumulation. Ppr1 mutation affected the Complex III activity in the electron transport chain and RNA editing of the mitochondrial gene ccmB. This study illustrates intron splicing as a key step in intronic miR400 production and highlights the function of intronic miRNAs as a 'signal transducer' in enhancing plant stress tolerance.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Cadmium (Cd) is a hazardous metal that can accumulate in aquatic organisms and endanger human health via the food chain. In this study, genetic engineering was used to display a peptide with ...Cd-binding potential on the surface of Escherichia coli cells. This whole-cell adsorbent exhibited high affinity for Cd ions (Cd2+) in the solution. The Cd2+ adsorption capacity of the whole-cell adsorbent was three-fold that of the control cells in a 20 μM Cd2+ solution, and 97.2% ± 2.38% of the Cd2+ was removed. The whole-cell adsorbent was fed to shrimp (Neocaridina denticulata), and the surface-engineered E. coli successfully colonized the shrimp intestine, which showed significantly less Cd accumulation than the group not fed surface-engineered E. coli. The whole-cell adsorbent evidently protected shrimp from the toxicity of Cd2+ by adsorbing it. Moreover, the whole-cell adsorbent mitigated the changes in microbial community structure in the shrimp gut caused by the exposure of Cd2+. These findings suggest that this strategy is effective for controlling the contamination of Cd2+ in shrimp.
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•A cell surface display system is used to improve the adsorption of Cd2+.•The whole-cell adsorbent exhibited efficient adsorption capacity for Cd2+.•Whole-cell adsorbent in shrimp gut facilitated Cd2+ excretion.•The surface-engineered E. coli reduced Cd2+ accumulation in shrimp tissue.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The crude processing of electronic waste (e-waste) has led to serious contamination in soils. While microorganisms may play a key role in remediation of the contaminated soils, the ecological effects ...of combined pollution (heavy metals, polychlorinated biphenyls, and polybrominated diphenyl ethers) on the composition and diversity of microbial communities remain unknown. In this study, a suite of e-waste contaminated soils were collected from Guiyu, China, and the indigenous microbial assemblages were profiled by 16S rRNA high-throughput sequencing and clone library analysis. Our data revealed significant differences in microbial taxonomic composition between the contaminated and the reference soils, with Proteobacteria, Acidobacteria, Bacteroidetes, and Firmicutes dominating the e-waste-affected communities. Genera previously identified as organic pollutants-degrading bacteria, such as Acinetobacter, Pseudomonas, and Alcanivorax, were frequently detected. Canonical correspondence analysis revealed that approximately 70% of the observed variation in microbial assemblages in the contaminated soils was explained by eight environmental variables (including soil physiochemical parameters and organic pollutants) together, among which moisture content, decabromodiphenyl ether (BDE-209), and copper were the major factors. These results provide the first detailed phylogenetic look at the microbial communities in e-waste contaminated soils, demonstrating that the complex combined pollution resulting from improper e-waste recycling may significantly alter soil microbiota.
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IJS, KILJ, NUK, PNG, UL, UM
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