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Self-healing covalent adaptable networks (CANs) are not only of fundamental interest but also of practical importance for achieving carbon neutrality and sustainable development. However, there is a trade-off between the mobility and cross-linking structure of CANs, making it challenging to develop CANs with excellent mechanical properties and high self-healing efficiency. Here, we report the utilization of a highly dynamic four-arm cross-linking unit with an internally catalyzed oxime-urethane group to obtain CAN-based ionogel with both high self-healing efficiency (>92.1%) at room temperature and superior mechanical properties (tensile strength 4.55 MPa and toughness 13.49 MJ m-3). This work demonstrates the significant potential of utilizing the synergistic electronic, spatial, and topological effects as a design strategy for developing high-performance materials. [ABSTRACT FROM AUTHOR]

The present paper reports the study of electrical characteristics and bias temperature stress (BT) stability of crystalline Indium‐Gallium oxide (IGO) dual‐gate thin film transistor (TFT) with top‐gate structure. TFT with normalized Ion over 100εA and PBTS/NBTIS of 0.35/‐2.85V was successfully fabricated. By adjusting oxygen partial pressure (O2%) and substrate temperature, we can control the wet etching rate (WER) of as‐deposited IGO film. After post annealing, crystalline IGO containing In2O3 phase with preferred orientation of (222) has been formed. The TFT characteristics uniformity and BT stability were found to depend on parameters of gate insulator (GI) deposition and pre‐treatment before GI. Based on experimental results, we propose high GI deposition temperature associated with low N2O plasma treatment power as the optimal condition for industrial production of crystalline IGO TFT. [ABSTRACT FROM AUTHOR]

WNK lysine deficient protein kinase 4 (WNK4) has been shown to be significantly associated with cancer progression. Nevertheless, its involvement in gastric cancer (GC) is unclear. the objective of this work was to investigate the WNK4's regulatory mechanism in GC. Quantitative RT-PCR and immunoblots revealed that WNK4 expression was downregulated in GC and that low expression of WNK4 was strongly linked to poor prognosis. Functional assays including cell counting kit-8 assay and colony formation assay demonstrated that overexpression of WNK4 led to limited tumor proliferation both in vitro and in vivo, while the WNK4 reduction yielded to the opposite results. Gene Set Enrichment Analysis (GSEA) indicated a potential association between WNK4 and the signal transducer and activator of transcription (STAT3). WNK4 suppressed the phosphorylation of signal transducer and activator of transcription 3 (p-STAT3) in GC cells. the inhibition of the STAT3 pathway with Stattic reversed growth and proliferation induced by WNK4 knockdown in GC cells. these findings provide new insights for identifying key therapeutic targets for GC in the future. [ABSTRACT FROM AUTHOR]

Sjögren’s syndrome (SjS) is a systemic, highly diverse, and chronic autoimmune disease with a significant global prevalence. It is a complex condition that requires careful management and monitoring. Recent research indicates that epigenetic mechanisms contribute to the pathophysiology of SjS by modulating gene expression and genome stability. DNA methylation, a form of epigenetic modification, is the fundamental mechanism that modifies the expression of various genes by modifying the transcriptional availability of regulatory regions within the genome. In general, adding a methyl group to DNA is linked with the inhibition of genes because it changes the chromatin structure. DNA methylation changes the fate of multiple immune cells, such as it leads to the transition of naïve lymphocytes to effector lymphocytes. A lack of central epigenetic enzymes frequently results in abnormal immune activation. Alterations in epigenetic modifications within immune cells or salivary gland epithelial cells are frequently detected during the pathogenesis of SjS, representing a robust association with autoimmune responses. The analysis of genome methylation is a beneficial tool for establishing connections between epigenetic changes within different cell types and their association with SjS. In various studies related to SjS, most differentially methylated regions are in the human leukocyte antigen (HLA) locus. Notably, the demethylation of various sites in the genome is often observed in SjS patients. The most strongly linked differentially methylated regions in SjS patients are found within genes regulated by type I interferon. This demethylation process is partly related to B-cell infiltration and disease progression. In addition, DNA demethylation of the runt-related transcription factor (RUNX1) gene, lymphotoxin-α (LTA), and myxovirus resistance protein A (MxA) is associated with SjS. It may assist the early diagnosis of SjS by serving as a potential biomarker. Therefore, this review offers a detailed insight into the function of DNA methylation in SjS and helps researchers to identify potential biomarkers in diagnosis, prognosis, and therapeutic targets. [ABSTRACT FROM AUTHOR]

Temperature probes onboard the Chang'E-4 (CE-4) spacecraft provide the first in situ regolith temperature measurements from the far side of the Moon. We present these temperature measurements with a customized thermal model and reveal the particle size of the lunar regolith at the CE-4 landing site to be ∼15 μm on average over depth, which indicates an immature regolith below the surface. In addition, the conductive component of thermal conductivity is measured as ∼1.53 × 10–3 W m–1 K–1 on the surface and ∼8.48 × 10–3 W m–1 K–1 at a depth of 1 m. The average bulk density is ∼471 kg m–3 on the surface and ∼824 kg m–3 in the upper 30 cm of the lunar regolith. These thermophysical properties provide important additional 'ground truth' at the lunar far side, which is critical for the future analysis and interpretation of global temperature observations. [ABSTRACT FROM AUTHOR]

In present paper, Lie group analysis is applied to consider vector field and symmetry reduction on forth-order time fractional KdV equation, power series solution and the convergence are investigated. Stability analysis of trivial solution to the reduction differential equation is showed by constructing appropriate Lyapunov function. Conservation laws of the equation are well constructed with a detailed derivation making use of Noether's operator. [ABSTRACT FROM AUTHOR]

Acquired resistance remains a key challenge in epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) therapy in lung adenocarcinoma (LUAD). Recent studies have shown that Notch signaling is associated with drug resistance. However, its role and possible mechanisms in EGFR-TKI resistance are not yet clear. In our study, we found that among four members of NOTCH1-4, only NOTCH3 was upregulated in LUAD tissues and TKI-resistant cell line (HCC827GR6). Knockdown of NOTCH3 by siRNA significantly inhibited proliferative ability, and decreased colony and sphere formation in HCC827GR6 cells. Then miR-150 was identified as a posttranscriptional regulator of NOTCH3. Its expression was downregulated in LUAD tissues and negatively correlated with NOTCH3 mRNA. The cell proliferation and IC50 of gefitinib were decreased in HCC827GR6 cells transfected with miR-150 mimic, but was reversed when cotransfected with NOTCH3 overexpressed vector. Moreover, we also enrolled 20 patients with advanced LUAD who have taken TKIs as first-line therapy in this study. We found that collagen 1A1 (COL1A1) expression was increased significantly in LUAD tissues both at mRNA and protein levels, and positively correlated with NOTCH3 expression verified in our data and TCGA data. Univariate survival analysis showed that patients with high protein expression of NOTCH3 or COL1A1 were associated with shorter overall survival (OS). Taken together, these results suggest that miR-150/NOTCH3/COL1A1 axis contributed to EGFR-TKI resistance in LUAD, which provide a potential therapeutic target for LUAD treatment. [ABSTRACT FROM AUTHOR]

In this work, polyvinyl pyrrolidone (PVP)-capped cadmium sulfide (denoted as PVP-capped CdS) nanopopcorns with tunable sizes and structures are prepared at different dose rates via one-step gamma-ray radiation-induced reduction. By means of modulating the dose rates in the synthetic process, we could control contents of hexagonal wurtzite (WZ) and cubic zinc blende (ZB) phases and the associated phase junction's distribution, aiming to achieve a type-II homojunction with a proper band alignment and effective separation of photoexcited electron-hole pairs. Under visible-light illumination, the PVP-capped CdS nanopopcorns with a size of 90 nm prepared at an optimal dose rate of 60 Gy min-1 show the best photoactivity (0.212 min-1) toward the degradation of rhodamine B in water as well as a H2 production rate of 3.52 mmol h-1 g-1 with cyclability. On the basis of the current results, the underlying crystal-growth and photocatalytic mechanisms are proposed. The one-step gamma-ray radiation-induced reduction approach is potentially applicable in the design and synthesis of a range of functional homojunction nanostructures for solar fuel production and environmental remediation. [ABSTRACT FROM AUTHOR]

The control in morphology and microstructure is an efficient approach to regulate the gas sensing properties of the sensor. In this work, polyaniline (PANi) layer in nanoscale film morphology was coated on the surface of reduced graphene oxide (rGO) sheets through the in situ polymerization method. The microstructure and properties of the composite sheets were characterized by scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectrometry, Raman spectrometry and thermal gravimetric analysis. It is found that there are strong effects of morphology-dependent structures of PANi layers on the sensing behaviors for ammonia detection, and more importantly, the utilization of the composite sheets as a new type of sensing material for highly sensitive detection of formaldehyde. Moreover, the best sensing properties can be achieved for the composite sheets with the thickness of PANi layer of 1.3 nm, benefiting from the strongest interaction between graphene sheet and PANi chains among all the composite sheets. Furthermore, a wide linear response range from 12 to 1500 ppm, 10 s response time for 100 ppm, 3.0 × 10−4/ppm sensitivity and 10 ppm detection limit can be achieved for ammonia, while 8 to 250 ppm, 35 s, 1.1 × 10−3/ppm and 4 ppm for formaldehyde. With the advantages in simplicity in material preparation and device operation as well as significant synergistic effects, PANi in nanoscale film morphology covered on the rGO sheets with large surface area can provide an efficient approach for fabricating sensitive and cheap chemiresistive sensor as an early warning system in some particular situations where either ammonia or formaldehyde is used widely or produced largely. [ABSTRACT FROM AUTHOR]

A novel amino-functionalized cellulose microsphere adsorbent (named C-VP) was prepared by radiation-induced grafting 4-vinyl pyridine (4VP) onto cellulose microsphere and subsequent protonation process. The graft polymerization conditions on the influence of grafting yield such as total absorbed dose, dose rate, solvent mixture ratio and monomer concentration, have been studied in detail. The obtained C-VP was tested for the abilities to remove Cr(VI) in batch experiments. The results demonstrated that the Cr(VI) adsorption was highly pH dependent and the maximum Cr(VI) uptake was obtained as the pH of solvent was 2.74. The adsorption isotherms of the C-VP for Cr(VI) fit the Langmuir model. The adsorption rate was considerably fast, and the adsorption reached equilibrium within 25 min. In addition, the Cr(VI) ions could be effectively desorbed using a 0.1 mol L–1 NaOH solution. Moreover, the reusability of the obtained C-VP was tested for several times and only slight loss in adsorption capacity was observed. Our work demonstrated the as-prepared adsorbent could possess a promising potential in the practical field of water treatment. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDCs) in monolayer form have attracted a great deal of attention for electronic and optical applications. Compared to mechanical exfoliation and chemical synthesis, laser thinning is a novel and unique “on-demand” approach to fabricate monolayers or pattern desired shapes with high controllability and reproducibility. Its successful demonstration motivates a further exploration of the dynamic behaviour of this local thinning process. Here, we present an in-situ study of void formation by laser irradiation with the assistance of temporal Raman evolution. In the analysis of time-dependent Raman intensity, an empirical formula relating void size to laser power and exposure time is established. Void in thinner MoS2 flakes grows faster than in thicker ones as a result of reduced sublimation temperature in the two-dimensional (2D) materials. Our study provides useful insights into the laser-thinning dynamics of 2D TMDCs and guidelines for an effective control over the void formation. [ABSTRACT FROM AUTHOR]

Background: Autogamy in cultivated tomato varieties is a derived trait from wild type tomato plants, which are mostly allogamous. However, environmental stresses can cause morphological defects in tomato flowers and hinder autogamy. Under elevated temperatures, tomato plants usually exhibit the phenotype of stigma exsertion, with severely hindered self-pollination and fruit setting, whereas the inherent mechanism of stigma exsertion have been hitherto unknown. Numerous small RNAs (sRNAs) have been shown to play significant roles in plant development and stress responses, however, none of them have been studied with respect to stamen and pistil development under high-temperature conditions. We investigated the associations between stigma exsertion and small RNAs using high-throughput sequencing technology and molecular biology approaches. Results: Sixteen sRNA libraries of Micro-Tom were constructed from plants stamen and pistil samples and sequenced after 2 d and 12 d of exposure to heat stress, respectively, from which a total of 110 known and 84 novel miRNAs were identified. Under heat stress conditions, 34 known and 35 novel miRNAs were differentially expressed in stamens, and 20 known and 10 novel miRNAs were differentially expressed in pistils. GO and KEGG pathway analysis showed that the predicted target genes of differentially expressed miRNAs were significantly enriched in metabolic pathways in both stamen and pistil libraries. Potential miRNA-target cleavage cascades that correlated with the regulation of stigma exsertion under heat stress conditions were found and validated through qRT-PCR and RLM-5'RACE. Conclusion: Overall, a global spectrum of known and novel miRNAs involved in tomato stigma exsertion and induced by high temperatures were identified using high-throughput sequencing and molecular biology approaches, laying a foundation for revealing the miRNA-mediated regulatory network involved in the development of tomato stamens and pistils under high-temperature conditions. [ABSTRACT FROM AUTHOR]

In the present paper, the Sawada-Kotera equation is considered by Lie symmetry analysis. All of the geometric vector fields to the Sawada-Kotera equation are obtained, and then the symmetry reductions and exact solutions of the Sawada-Kotera equation are investigated. Our results show that symmetry analysis is a very efficient and powerful technique in finding the solution of the proposed equation. [ABSTRACT FROM AUTHOR]

In the present paper, the Sharma-Tasso-Olever (STO) equation is considered by the Lie symmetry analysis. All of the geometric vector fields to the STO equation are obtained, and then the symmetry reductions and exact solutions of the equation are investigated. Our results witness that symmetry analysis is a very efficient and powerful technique in finding the solutions of the proposed equation. [ABSTRACT FROM AUTHOR]

DNA double-strand break (DSB) repair is not only key to genome stability but is also an important anticancer target. Through an shRNA library-based screening, we identified ubiquitin-conjugating enzyme H7 (UbcH7, also known as Ube2L3), a ubiquitin E2 enzyme, as a critical player in DSB repair. UbcH7 regulates both the steady-state and replicative stress-induced ubiquitination and proteasome-dependent degradation of the tumor suppressor p53-binding protein 1 (53BP1). Phosphorylation of 53BP1 at the N terminus is involved in the replicative stress-induced 53BP1 degradation. Depletion of UbcH7 stabilizes 53BP1, leading to inhibition of DSB end resection. Therefore, UbcH7-depleted cells display increased nonhomologous end-joining and reduced homologous recombination for DSB repair. Accordingly, UbcH7-depleted cells are sensitive to DNA damage likely because they mainly used the error-prone nonhomologous end-joining pathway to repair DSBs. Our studies reveal a novel layer of regulation of the DSB repair choice and propose an innovative approach to enhance the effect of radiotherapy or chemotherapy through stabilizing 53BP1. [ABSTRACT FROM AUTHOR]

This paper presents the formulation of the time-fractional generalized Korteweg-de Vries equation (KdV) using the Euler-Lagrange variational technique in the Riemann-Liouville derivative sense and derives an approximate solitary wave solution. Our results show that He's variational-iteration method is a very efficient technique for finding the solution of the proposed equation and extend the existing results. [ABSTRACT FROM AUTHOR]

We consider the existence of positive solution for a third-order singular generalized left focal boundary value problem with full derivatives in Banach spaces. Green's function and its properties, explicit a priori, estimates will be presented. By means of the theories of the fixed point in cones, we establish some new and general results on the existence of single and multiple positive solutions to the third-order singular generalized left focal boundary value problem. Our results are generalizations and extensions of the results of the focal boundary value problem. An example is included to illustrate the results obtained. [ABSTRACT FROM AUTHOR]

In order to investigate the effects of the non-solvent species on the formation mechanism of polyacrylonitrile (PAN) fiber in wet spinning, theoretical ternary phase diagrams of water/DMSO/PAN and ethanol/DMSO/PAN systems were constructed based on the extended Flory-Huggins theory. The cloud-points of dilute PAN solutions of the two systems were determined by titration method and those of concentrated PAN solutions from Boom's linearized cloud-point correlation. Binary interaction parameters were calculated and optimized to construct the theoretical phase diagram. The obtained diagrams were used to investigate the effects of the non-solvent species on the formation of PAN fibers. If the non-solvent water is replaced with ethanol, the meta-stable two-phase region in the ternary phase diagram increases. This favors the de-mixing of the filament via nucleation and growth mechanism during the coagulation process, resulting in homogenous dense PAN fibers with low porosity. [ABSTRACT FROM AUTHOR]

By using the functional type cone expansion and compression fixed-point theorem in cones, some new and general results on the existence of positive solution for twin singular boundary value problems with damping term are obtained. An example is given to illustrate our results. [ABSTRACT FROM AUTHOR]

By applying the fixed point theorem in cones, a new and general result on the existence of positive solutions to second-order generalized Sturm-Liouville boundary value problem on a time scale  is obtained. The first order Δ-derivative is involved in the nonlinear term f explicitly. [ABSTRACT FROM AUTHOR]

The jet stretch of wet‐spun PAN fiber and its effects on the cross‐section shape and properties of fibers were investigated for the PAN‐DMSO‐H2O system. Evidently, the spinning parameters, such as dope temperature, bath concentration, and bath temperature, influenced the jet stretch. Also, under uniform conditions, the postdrawing ratio changed as well as that of jet stretch. When coagulation temperature was 35°C simultaneously with bath concentration of 70%, jet stretch impacted obviously the cross‐section shapes of PAN fiber, but had little effect when the temperature was below 10°C or above 70°C. As the jet stretch ratio increased, the crystallinity, crystal size, sonic orientation, and mechanical properties of the as‐spun fiber changed rapidly to a major value for jet stretch ratio of 0.9 where the cross section of as‐spun fiber was circular. With further increasing of jet stretch ratio, the properties changed slightly but the fiber shape was not circular. The results indicated that appropriate jet stretch, under milder formation conditions in wet‐spinning, could result in the higher postdrawing ratio and circular profile of PAN fiber, which were helpful to produce round PAN precursor with minor titer and perfect properties for carbon fiber. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [ABSTRACT FROM AUTHOR]

Due to the mismatch between an overlay and its underlying physical network, the routing latency in existing DHT systems such as Chord and CAN is rather high. We note the fact that the IPv6 address hierarchical structure can aggregate route entries in Internet, and thus propose that nodes in an overlay can cluster together by taking advantage of the shared IPv6 prefix of specific length. While utilizing DHT systems themselves to store and retrieve the IPv6 prefix information, we adapt it to Chord and thus construct an improved version dubbed eChord. Analysis and simulation results confirm that eChord can significantly reduce routing latency. [ABSTRACT FROM PUBLISHER]

Graphene-based optoelectronic devices, including reduced graphene oxide (RGO) devices, commonly exhibit a large dark current and low on/off ratio with high dark-power consumption and a small responsivity. In this study, semi-RGO-based infrared photodetectors were directly “written” by using lasers, which can exhibit a small dark current of approximately 12 µA/cm2 with a high responsivity of approximately 0.18 A/W at 1,550 nm. Both the dark current and response speed can be tuned with GO as the gate dielectric in a field-effect transistor structure. These findings suggest the possibility of the three-dimensional “writing” of a micro-optoelectronic device or system with a low cost and high performance. [ABSTRACT FROM AUTHOR]