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Ionic liquids (ILs) have attracted increasing attention since last few decades due to their high molecular design abilities and wide applications in different fields. In this study, four novel fluorescent isoquinolino [2,1-a]quinoxalin-5-ium ILs were designed and synthesized via a two-step process including a simple dual Schiff's base formation and a subsequent [RhCp∗Cl2]2-catalyzed oxidative C–H activation/annulation reaction. The as-synthesized ILs were extensively characterized using FT-IR, 1H-NMR, 13C-NMR, 19F-NMR, HSQC-NMR, HMBC-NMR and HR-MS. Their photophysical properties were determined by steady-state fluorescence spectroscopy. The results demonstrate that all these ILs showed dual or triple emissions, large stokes shift (90 nm) and mechanochromic behaviors. Basing on solvatochromism and titration experiments, it is thought that the emission bands of the ILs are raised from their local excited states, charge transfer states or excited state proton transfer of cations, while the substitute effect of these quinoxaline derived ILs on their stokes shifts is negligible.

Comprehensive utilization of stainless-steel slag (SSS) is restrained due to the risk of Cr6+ leaching. Based on the studying the microstructure of synthetic slag (SS) containing Cr2O3 with XRD, SEM-EDS, and Image pro, the effect of binary basicity on the chromium occurrence in SSS was investigated. The results indicated that the binary basicity had a significant impact on the properties of spinel crystals. There was a positive correlation between the calcium content in spinel crystals and the SS basicity. The size of spinel crystals varied from large to small and the precipitation occurrence changed with the basicity increase. Furthermore, the chromium occurrences changed with the basicity. The chromium was produced in spinel crystals at lower basicity, but as the basicity increased to 3.0, the chromium precipitated as calcium chromate. In view of the relationship between the chromium leaching behavior and its occurrence, increasing basicity raised the Cr6+ leaching.

In order to explore effects of long-chain non-coding ribonucleic acid (RNA) HOTAIR on proliferation and migration of human lens epithelial cells, SRA01/04 cells were selected as the research strain in this study and divided into S1 group (no HOTAIR transfection), S2 group (siHOTAIR transfection), S3 group (siHOTAIR+10 ng/mL TGF-β2), and S4 group (no HOTAIR transfection+10 ng/mL TGF-β2) according to the presence or absence of transforming growth factor (TGF)-β2 and silent HOTAIR treatment. 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide (MTT) colorimetric method was applied to detect cell proliferation.Western blot was used for detection of E-cadherin, zonula occluden-1 (ZO-1), Vimentin, α-smooth muscle actin (SMA), Snail, Slug, zinc finger E-box binding homeobox 1 (ZEB1), and Smad-2 expressions. Results showed that the number of transmembrane cells in S4 group was higher markedly than that of the other groups, but that of S2 group dropped steeply compared with the other groups (P α-SMA (0.64±0.28) decreased sharply compared with the other groups (P < 0.05); Snail (2.51±0.59), Slug (2.11±0.47), and ZEB1 (2.83±0.53) of S4 group rose obviously compared with the other groups, but the above of S2 group reduced hugely compared with the other groups (P < 0.05); pSmad-2 and pSmad-3 of S4 group elevated greatly compared with the other groups, and those of S2 group reduced hugely compared with the other groups (P < 0.05). In conclusion, HOTAIR high expression could promote TGF-β2-induced SRA01/04 cell proliferation, migration, invasion, and epithelial-mesenchymal trans-differentiation, which was related to TGF-β/Smad signaling pathway.

Studies have shown the electron shuttling role of humic substances (HS) in enhancing microbial reduction of solid-phase Fe(III), but it is unknown if native HS can reduce structural Fe(III) in clays and how their chemical properties affect this process and secondary mineralization. The objective of this study was to evaluate the role of natural HS, Leonardite humic acid (LHA), and Pahokee Peat humic acid (PPHA) in reducing structural Fe(III) in nontronite with or without Shewanella putrefaciens. The extent of Fe(III) reduction was determined with a wet chemical method. Electrochemical methods, spectroscopy, and mass spectrometry were used to determine the changes of HS electrochemical and molecular composition after bioreduction. X-ray diffraction and electron microscopy were used to observe mineralogical transformations. The results showed that natural HS not only served as an electron donor to abiotically reduce Fe(III) in nontronite but also served as an electron shuttle to enhance Fe(III) bioreduction by S. putrefaciens. In the presence of CN32 cells, both the rate and extent of Fe(III) reduction significantly increased. Between the two HS, PPHA was more effective. The final bioreduction extents were 12.2 and 17.8% with LHA and PPHA, respectively, in bicarbonate buffer. Interestingly, when CN32 cells were present, LHA and PPHA donated more electrons to NAu-2, suggesting that CN32 cells were able to make additional electrons of LHA and PPHA available to reduce structural Fe(III). Although LHA reduced less Fe(III), it induced more extensive mineral transformation. In contrast, PPHA reduced more Fe(III) but did not induce any mineralogical change. These contrasting behaviors between the two humic acids are ascribed to their differences in electron-donating capacity, reactive functional group distribution, and metal complexation capacity. A unique set of secondary minerals, including talc, illite, silica, albite, ilmenite, and ferrihydrite formed as a result of reduction. The results highlight the importance of coupled C and Fe biogeochemical transformations and have implications for nutrient cycling and contaminant migration in the environment.

In order to meet the requirements of sustainable development, the production of aromatic compounds from renewable biomass is of great concern. Herein, a surfactant-free microemulsion (SFME) system ...

Reduced nontronite has been demonstrated to be antibacterial through the production of hydroxyl radical (•OH) from the oxidation of structural Fe(II). Herein, we investigated the antibacterial activity of more common smectite-illite (S-I) clays toward Escherichia coli cells, including montmorillonite SWy-3, illite IMt-2, 50-50 S-I rectorite RAr-1, 30-70 S-I ISCz-1, and nontronite NAu-2. Under an oxic condition, reduced clays (with a prefix r before mineral names) produced reactive oxygen species (ROS), and the antibacterial activity followed the order of rRAr-1 > rSWy-3 ≥ rNAu-2 ≫ rIMt-2 ≥ rISCz-1. The strongest antibacterial activity of rRAr-1 was contributed by a combination of •OH and Fe(IV) generated from structural Fe(II)/adsorbed Fe2+ and soluble Fe2+, respectively. Higher levels of lipid and protein oxidation, intracellular ROS accumulation, and membrane disruption were consistent with this antibacterial mechanism of rRAr-1. The antibacterial activity of other S-I clays depended on layer expandability, which determined the reactivity of structural Fe(II) and the production of •OH, with the expandable smectite being the most antibacterial and nonexpandable illite the least. Our results provide new insights into the antibacterial mechanisms of clay minerals.

NAZ2329 is the first cell-permeable small molecular allosteric inhibitor of protein tyrosine phosphatase receptor–type Z (PTPRZ), which was considered as a new potential molecular target for drug development in glioblastoma. A facile and high-efficient synthesis of NAZ2329 was developed by a straight-forward strategy starting from key ethoxy benzyl bromide intermediate obtained from commercially available 4-(trifluoromethyl)phenol.

To obtain an alkali-free glass substrate with enhanced properties for thin-film transistor–liquid crystal displays (TFT–LCDs) applications, we chose a base glass composed of 3B2O3-15Al2O3-58SiO2-22MgO-0.5SrO-1.5MgF2 (mol%) for nucleation–crystallization. The results show that when the nucleation–crystallization processes of the base glass are 810 °C/6 h + 880 °C/6–9 h, the prepared GC/6–GC/9 glass-ceramics exhibit enhanced properties because of the precipitation of nano-sized cordierite. The transmittances in the visible range of the GC/6–GC/9 glass-ceramics exceed 85%, the densities are 2.564–2.567 g/cm3, thermal expansion coefficients are 2.934–3.059 × 10-6/°C (25–300 °C), compressive strengths are 417–589 MPa, bending strengths are 141–259 MPa, Vickers hardnesses are 6.8–7.8 GPa, and strain points are approximately 735 °C. Considering these properties, the prepared GC/6–GC/9 glass-ceramics have good potential as candidate materials for alkali-free glass substrates. Additionally, these results demonstrate that it is feasible to improve the properties of alkali-free glass substrates by nucleation–crystallization.

Lignin is a major component of plant-derived soil organic matter (SOM) in soils and sediments. Fe-bearing clay minerals are widely distributed in these environments and often co-exist with lignin. While previous studies have reported the electron shuttling and donating roles of certain redox-active SOM in the dissimilatory reduction of structural Fe(III) in Fe-bearing clay minerals, the role of lignin in this process remains unknown. Here we studied this role by incubating an Fe-rich smectite (nontronite NAu-2) with two types of lignin (soluble and insoluble) in the absence and presence of an Fe(III)-reducing bacterium Shewanella putrefaciens CN32 under anaerobic condition. Lactate was added in some experiments as an extra electron donor. The results demonstrated that both soluble and insoluble lignins abiotically reduced structural Fe(III) in NAu-2. The reduction extent was proportional to lignin concentration. After abiotic reaction, lignin served as either electron shuttle or electron donor in the presence of CN32: (1) When lactate was present, lignin served as an electron shuttle to enhance the rate of Fe(III) reduction; (2) When lactate was absent, lignin served as an electron donor for Fe(III) reduction. Although the ultimate biotic Fe(III) reduction extents were similar in the presence of either soluble or insoluble lignin, the reduction rates with soluble lignin were higher than those with insoluble lignin, likely owing to their different electron transfer mechanisms. After interaction with NAu-2 and/or CN32, soluble lignin structure largely remained intact, but with some decreases of humic/fulvic acid-like and protein-like compounds, aromatic functional groups (e.g., C H, C O, COOH), and aliphatic/aromatic compounds. An increase of semiquinone-like organic radicals was observed after lignin interaction with NAu-2. These chemical changes of lignin were likely coupled with the reduction of structural Fe(III) in nontronite. Upon reduction, the nontronite did not display much dissolution and mineral transformation. The findings of this study provide insights into the role of lignin in promoting mineral-microbe interactions and have significant implications for coupled Fe and C biogeochemical cycles in soils and sediments.

Geopolymer-based materials have attracted increasing interest in construction and infrastructure engineering due to their high mechanical properties but low carbon dioxide emissions. However, it remains unclear whether this type of material can work in a stable way in harsh environments. This study investigated the chemical–physical–mechanical stability of metakaolin-based geopolymer (MKG) mortars under the immersing actions of sodium sulfate and magnesium sulfate solutions up to 180 days by testing their visual appearance, mass, dimensions, strength, microstructure and chemical components. Results show that the immersion actions do not cause obvious changes in mass, dimensions or compressive and flexural strengths of the MKG mortars. A white deposit, consisting of magnesium hydroxide, magnesium sulfate, magnesium carbonate and magnesium silicate aluminate hydrate, appeared on the surfaces of the high-alkali MKG specimens immersed in magnesium sulfate solution for 30 days, and disappeared at later ages due to the continual consumption of magnesium hydroxide. Mg–Na exchanges occurred for the MKG mortars immersed in magnesium sulfate solution. Overall, the chemical–physical–mechanical stability of geopolymer-based materials depends on the material components and interactions with the environment. Caution should be used before any engineering applications, and relevant issues deserve further rigorous investigation in the future.

Turnover of soil organic carbon (SOC) is strongly affected by a balance between mineral protection and microbial degradation. However, the mechanisms controlling the heterogeneous and preferential adsorption of different types of SOC remain elusive. In this work, the heterogeneous adsorption of humic substances (HSs) and microbial carbon (MC) on a clay mineral (nontronite NAu-2) during microbial-mediated Fe redox cycling was determined using time-of-flight secondary ion mass spectrometry (ToF-SIMS). The results revealed that HSs pre-adsorbed on NAu-2 would partially inhibit structural modification of NAu-2 by microbial Fe(III) reduction, thus retarding the subsequent adsorption of MC. In contrast, NAu-2 without precoated HSs adsorbed a significant amount of MC from microbial polysaccharides as a result of Fe(III) reduction. This was attributed to the deposition of a thin Al-rich layer on the clay surface, which provided active sites for MC adsorption. This study provides direct and detailed molecular evidence for the first time to explain the preferential adsorption of MC over HSs on the surface of clay minerals in iron redox processes, which could be critical for the preservation of MC in soil. The results also indicate that ToF-SIMS is a unique tool for understanding complex organic-mineral-microbe interactions.

Reliability remains an issue for the Si/SiC hybrid switch adopting the conventional switching strategy of the internal SiC MOSFET that turns on earlier, and off later. Such issue is attributable to the overcurrent stress under the heavy load operating condition, which adversely affects the SiC MOSFET during the gate delay time. To solve this problem without increasing the extra power loss, a novel variable-frequency current-dependent switching strategy combining the variable switching pattern strategy, and the variable pulsewidth modulation (PWM) frequency strategy is proposed. Variable switching pattern strategy can avoid the overcurrent stress of the SiC MOSFET at the heavy load operating condition, and the designed optimal delay time in different switching patterns can achieve the compromise between the excellent reliability, and the power loss of Si/SiC hybrid switch. Variable PWM frequency strategy can effectively reduce the switching loss of the Si/SiC hybrid switch by decreasing the switching frequency around the peak current region. An Si/SiC-hybrid-switch-based single-phase inverter platform is constructed and tested. Test results show that the power loss of the single-phase inverter adopting such switching strategy outperforms the current-dependent switching strategy with 9.4% reduction of power loss, and overcurrent stress of SiC MOSFET is avoided.

The power conversion efficiency for single-junction solar cells is limited by the Shockley-Quiesser limit. An effective approach to realize high efficiency is to develop multi-junction cells. These years have witnessed the rapid development of organic–inorganic perovskite solar cells. The excellent optoelectronic properties and tunable bandgaps of perovskite materials make them potential candidates for developing tandem solar cells, by combining with silicon, Cu(In,Ga)Se2 and organic solar cells. In this review, we present the recent progress of perovskite-based tandem solar cells, including perovskite/silicon, perovskite/perovskite, perovskite/Cu(In,Ga)Se2, and perovskite/organic cells. Finally, the challenges and opportunities for perovskite-based tandem solar cells are discussed.

Carbon dioxide (CO2) pretreatment to concrete at the early curing ages is a feasible technique towards achieving a greener and more sustainable concrete industry. However, the carbonation efficienc...

Surface plasmon resonance microscopy (SPRM) has been widely used as a sensitive imaging platform for chemical and biological analysis. The SPRM system inevitably suffers from focus inhomogeneity and drifts, especially in long-term recordings, leading to distorted images and inaccurate quantification. Traditional focus correction approaches require additional optical parts to detect and adjust focal conditions. Herein, we propose a deep-learning-based image processing method to gain autofocused SPRM images, without increasing the complexity of the optical systems. We trained a generative adversarial network (GAN) model with thousands of SPRM images of nanoparticles acquired at different focal distances. The trained model was able to directly generate focused SPRM images from single-shot defocused images, with no prior knowledge of the focus conditions during recording. Experiments using Au nanoparticles show that this method is effective in both static and time-lapse monitoring. The proposed autofocus technique thus provides an approach for improving the consistency among SPRM studies and for long-term monitoring.

The efficient conversion of solar energy to electricity for human utilization heavily relies on the development of solar cells. Nowadays, a variety of high-performance solar cells are constantly emerging. Thin-film solar cells made from inorganic materials have constituted one of the major categories of solar cells showing potential in the fast growing photovoltaic (PV) market. In order to provide an overall grasp of and insight into the future direction of inorganic thin-film solar cell development, we review key emerging and representative inorganic photovoltaic materials including chalcopyrite Cu(In,Ga)Se2 (CIGSe), kesterite Cu2ZnSn(S,Se)4 (CZTSSe), CdTe, Sb2Se3 and inorganic perovskite CsPb(I1−xBrx)3 in this paper. Absorber materials, evolution of device development, and current challenges and key strategies for performance enhancement are detailed.

Tuning microstructures by adding nanoparticles is a promising way of improving the performance of cementitious composites. In this study, nanoclay was introduced to polyvinyl alcohol (PVA) fiber reinforced ultra high toughness cementitious composites (UHTCCs). The mechanical properties, crack patterns, water permeation resistance, and microstructures of UHTCCs with different dosages of nanoclay were studied. The addition of a proper dosage of nanoclay shows few effects on the compressive strength of UHTCCs, however, the compressive strength is decreased when an excessive amount of nanoclay is added. The flexural deformation capacity of UHTCCs is independent of nanoclay dosage, whereas the flexural strength generally decreases with an increasing dosage of nanoclay. Different cracking patterns were observed in the ultra high toughness cementitious composites containing nanoclay (NC-UHTCC) specimens subject to bending tests. A UHTCC with 1% (in weight) nanoclay shows the best water permeation resistance and the lowest water permeability. Variations in the mechanical properties and the water permeation resistance of UHTCCs containing different dosages of nanoclay could be ascribed to the synthetic effects of filling and heterogeneous nucleation of nanoclay at low dosages and the agglomeration effect of nanoclay at high dosages. This study is to optimize the water permeation resistance of UHTCCs, paving a path for the future application of UHTCCs in the fields of construction, decoration, and repair.

A Pd-catalyzed regio- and stereoselective alkynylallylation of a specific C-C σ bond in cyclopropenes, using allyl propiolates as both allylation and alkynylation reagents, has been achieved for the first time. By merging selective C(sp2 )-C(sp3 ) bond scission with conjunctive cross-couplings, this decarboxylative reorganization reaction features fascinating atom and step economy and provides an efficient approach to highly functionalized dienynes from readily available substrates. Without further optimization, gram-scale products can be easily obtained by such a simple, neutral, and low-cost catalytic system with high TONs. DFT calculations afford a rationale toward the formation of the products and indicate that the selective insertion of the double bond of cyclopropenes into the C-Pd bond of ambidentate Pd complex and the subsequent nonclassical β-C elimination promoted by 1,4-palladium migration are critical for the success of the reaction.

Background: Hydrogen sulfide (H 2 S) has antihypertension and anti-inflammatory effects, and its endogenous-generation key enzyme cystathionine γ lyase (CSE) is expressed in CD4 + T cells. However, the role of CD4 + T-cell endogenous CSE/H 2 S in the development of hypertension is unclear. Methods: Peripheral blood lymphocytes were isolated from hypertensive patients or spontaneously hypertensive rats, then H 2 S production and expression of its generation enzymes, cystathionine β synthase and CSE, were measured to determine the major H 2 S generation system changes in hypertension. Mice with CSE-specific knockout in T cells (conditional knockout, by CD4 cre mice hybridization) and CD4 null mice were generated for investigating the pathophysiological relevance of the CSE/H 2 S system. Results: In lymphocytes, H 2 S from CSE, but not cystathionine β synthase, responded to blood pressure changes, supported by lymphocyte CSE protein changes and a negative correlation between H 2 S production with systolic blood pressure and diastolic blood pressure, but positive correlation with the serum level of interleukin 10 (an anti-inflammatory cytokine). Deletion of CSE in T cells elevated BP (5–8 mm Hg) under the physiological condition and exacerbated angiotensin II–induced hypertension. In keeping with hypertension, mesenteric artery dilation impaired association with arterial inflammation, an effect attributed to reduced immunoinhibitory T regulatory cell (Treg) numbers in the blood and kidney, thus causing excess CD4 + and CD8 + T cell infiltration in perivascular adipose tissues and kidney. CSE knockout CD4 + T cell transfer into CD4 null mice, also showed the similar phenotypes’ confirming the role of endogenous CSE/H 2 S action. Adoptive transfer of Tregs (to conditional knockout mice) reversed hypertension, vascular relaxation impairment, and immunocyte infiltration, which confirmed that conditional knockout–induced hypertension was attributable, in part, to the reduced Treg numbers. Mechanistically, endogenous CSE/H 2 S promoted Treg differentiation and proliferation by activating AMP-activated protein kinase. In part, it depended on activation of its upstream kinase, liver kinase B1, by sulfhydration to facilitate its substrate binding and phosphorylation. Conclusion: The constitutive sulfhydration of liver kinase B1 by CSE-derived H 2 S activates its target kinase, AMP-activated protein kinase, and promotes Treg differentiation and proliferation, which attenuates the vascular and renal immune-inflammation, thereby preventing hypertension.

Hydroxyl radicals (·OH) exert a strong impact on the carbon cycle due to their nonselective and highly oxidizing nature. Reduced iron-containing clay minerals (RIC) are one of the major contributors to the formation of ·OH in dark environments, but their interactions with humic acids (HA) are poorly known. Here, we investigate the mutual interactions between RIC and HA under dark and oxygenated conditions. HA decreased the oxidation rate of structural Fe(II) in RIC but significantly promoted the ·OH yield. HA dissolved a fraction of Fe(II) from RIC to form an aqueous Fe(II)-HA complex. ·OH were generated through both heterogeneous (through oxidation of structural Fe(II)) and homogeneous pathways (through oxidation of aqueous Fe(II)-HA species). RIC-mediated ·OH production by providing H2O2 to react with Fe(II)-HA and electrons to regenerate Fe(II)-HA. This highly efficient homogeneous pathway was responsible for increased ·OH yield. Abundant ·OH significantly decreased the molecular size, bleached chromophores, and increased the oxygen-containing functional groups of HA. These molecular changes of HA resembled photochemical transformation of HA. The mutual interaction between RIC and HA in dark and redox-fluctuating environments provides a new pathway for fast turnover of recalcitrant organic matters in clay- and HA-rich ecosystems such as tropical forest soils and tidal marsh sediments.

Catalytic conversion of lignin to versatile aromatic compounds is attracting increasing attention. However, it is highly desirable but challenging to produce a specific chemical with high yield thr...

Nanopore analysis based on a resistive-pulse technique is an attractive tool for single-molecule detection in different fields, but it suffers a great drawback in selectivity. A common solution to this challenge is to add extra sensing aptamers and labels to analytes by improving the sensitivity of their pulses for distinguishing. Compared to the labeling methods, we alternatively develop and demonstrate a novel data process for label-free nanopore analysis that enables the conversion of resistive current signals to more specific frequency domain phase angle features with the contribution from both sinusoidal voltage excitation and Fourier transform. In particular, we find that the transmural capacitance induced by nanoparticle translocations under a sinusoidal voltage plays an important role in this process, making phase angle features more pronounced. In practical applications, the method is successfully applied to directly distinguish the translocation events through a nanopipette by their unique phase angles for similarly sized SiO2, Ag, and Au nanoparticles and soft living organisms of HeLa and LoVo and even in a more complicated case of a SiO2, Ag, and Au nanoparticle mixture.

Lime mortar with organic additives is one of the most widely used building materials in ancient China and continues to play an important role in historic structure restoration. This study investigated the erosion of ordinary aerial lime and sticky-rice mortars under the cyclic actions of wetting–drying (WD) and dilute sulfate acid (DSA). Comprehensive experimental tests were conducted to study the mechanical properties, quality, microstructure and pore structure of the mortars according to cyclic WD and DSA actions. Results showed that both the WD and DSA actions can significantly degrade the compressive and shear strengths of the mortars. The DSA softens the mortar matrices more severely than the WD by a leaching mechanism. Apparently, sticky rice does not change the micro morphology, pore structure and packing pattern of the mortar matrices, but it inhibits the carbonation of the lime. Both the WD and DSA actions can erode the ordinary aerial lime and sticky-rice mortars, causing more porous matrices and coarser particles. The results of this study make it possible to clarify how the WD and DSA actions affect the durability of partially matured aerial lime mortars with or without sticky rice, with potential uses in the restoration of ancient buildings.

Berberine chloride (BBC) is a well-known plant isoquinoline alkaloid derived from Berberis aristata. In this study, we aim to explore the effect of BBC on non-small cell lung cancer (NSCLC), and further expound the underlying mechanism of BBC induces NSCLC cell death in vitro and in vivo. CCK-8 assay and colony formation assay were used to test the viability and colony formation ability of NSCLC cells. Apoptosis analysis was used to analyze the apoptotic cells. siRNAs were utilized to disturb the expression of Sin3A. qPCR and Western blot analysis were employed to determine mRNA and protein levels of related genes and proteins. Tumor xenografts model was used for in vivo detection. BBC inhibited the proliferation and colony formation of human NSCLC cells in a dose- and time-dependent manner. In addition, BBC induced DNA double-stranded breaks (DSBs) through downregulating TOP2B level, leading to apoptosis in human NSCLC cells. The Chip-seq data of A549 cells obtained from the ENCODE consortium indicate that Sin3A binds on the promoters of TOP2B. Knockdown of Sin3A led to downregulation of TOP2B in human NSCLC cells. Furthermore, BBC decreased Sin3A expression and shortened the half-life of Sin3A, results in downregulation of TOP2B in human NSCLC cells. In this study, we demonstrated a new mechanism that BBC suppresses human NSCLC by deregulating Sin3A/TOP2B pathway, leading to DNA damage and apoptosis in human NSCLC in vitro and in vivo.

The global impact of malaria remains staggering despite extensive efforts to eradicate the disease. With increasing drug resistance and the absence of a clinically available vaccine, there is an urgent need for novel, affordable, and safe drugs for prevention and treatment of malaria. Previously, we described a novel antimalarial acridone chemotype that is potent against both blood-stage and liver-stage malaria parasites. Here, we describe an optimization process that has produced a second-generation acridone series with significant improvements in efficacy, metabolic stability, pharmacokinetics, and safety profiles. These findings highlight the therapeutic potential of dual-stage targeting acridones as novel drug candidates for further preclinical development.

Novel gas-responsive imprinting hydrogels were fabricated by combining N,N′-dimethylaminoethyl methacrylate gas-sensitive monomers, N,N′-methylenebis(acrylamide) cross-linkers, and human serum albu...

Organic matter (OM) is often associated with Fe (hydr)oxides such as ferrihydrite (Fh) in soils and sediments, forming binary Fh-OM complexes. Microbial reduction of Fh results in destabilization of the complexes and mineral/OM transformation. However, little is known about the role of clay minerals in such processes, despite their common co-existence with Fh and OM in natural environments. Here Fh-OM complexes were synthesized in the presence of montmorillonite (SWy-2), forming ternary Fh-(SWy-2)-OM complexes. A metal-reducing bacterium Geobacter sulfurreducens was used to reduce Fh in the complexes under circumneutral pH and anoxic conditions with or without H2 as extra electron donor. Various spectroscopy and mass spectrometry methods were used to monitor the progress of Fh bio-reduction and mineral/OM transformation. Results showed that G. sulfurreducens utilized mineral-bound OM as electron donor and/or carbon source to couple with Fh reduction. Relative to Fh-OM complex, addition of SWy-2 to Fh-OM complex enhanced the bio-reduction extent of Fh by increasing the proportion of bioavailable OM that was weakly bound to SWy-2. However, its effect on the bio-reduction rate was variable. SWy-2 initially decreased the rate, because it spatially separated OM (electron donor) from Fh (electron acceptor). During later incubation, SWy-2 increased the reduction rate by sorbing biogenic Fe2+ that would otherwise passivate the Fh and cell surfaces. Bio-reduction transformed mineral-bound OM to microbial products (e.g. necromass, extracellular polymeric substances), but organic compounds with aromatic structures, carboxyl groups and large molecular weight were more resistant to desorption and oxidation. The persistence of these compounds against bio-reduction induced transformation is likely due to their stronger binding with minerals and/or lower nominal oxidation states of carbon relative to other compounds. Our results provide new insights into the role of clay minerals in regulating biogeochemical cycling of solid-phase Fe and transformation of mineral-associated OM in anoxic soil environments.

In order to improve the recycling efficiency of stainless-steel slag resources, the effect of different cooling rates on the crystallization behavior of CaO-SiO2-MgO-Cr2O3 based system was studied by using FactSage 7.1, XRD, SEM and IPP 6.0. The results indicated that the spinel is a high-temperature precipitated phase and the cooling rate had less effect on the final grain size of spinel crystals, but had greater influences on the nucleation of spinel crystals and the crystallization of silicates such as α-C2S.When the cooling rate was 12∘C/min, the spinel crystals was the unique precipitation. However, the spinel crystals and α-C2S could produce during the slag cooling process as the cooling rate was1∘C/min. Chromium in silicate phase is inclinable to leaching with the dissolution of silicate phase, so the formation of silicate phase should be controlled. According to the influence of the cooling rate on the formation of spinel crystals and the erosion of spinel crystals by α-C2S, it is suggested that the cooling rate of the stainless-steel slag in industrial treatment should not be lower than 12∘C/min.

The silicon (Si)/silicon carbide (SiC) hybrid switch comprising a Si insulated gate bipolar translator (IGBT) and a SiC metal-oxide-semiconductor field effect transistor (MOSFET) in parallel offers not only excellent performance and cost tradeoff but also inherent switch-level redundancy for potential power converter fault-tolerant operation. It is possible to operate the power converter even when either the SiC MOSFET or the Si IGBT experiences an open-circuit fault. This article first analyzes various switch failure scenarios and then proposes a novel fault-tolerant control strategy for a single-phase inverter based on the Si/SiC hybrid switches to mitigate a single-point switch failure and maintain inverter operation. Experimental results validate the effectiveness of the proposed fault-tolerant control strategy.

A discrete tetrahedral indium cage, {[In12(μ3-OH)4(HCO2)24(tcma)4]} (In12-GL), was synthesized solvothermally by the reaction of indium nitrate with the tripodal tricarboxylic acid ligand N,N,N-tri...

Electrochemical oxidation is a promising and effective method for lignin depolymerization owing to its selective oxidation capacity and environmental friendliness. Herein, the electrooxidation of non-phenolic alkyl aryl ether monomers and β-O-4 dimers was experimentally (by cyclic voltammetry, in situ spectroelectrochemistry, and gas chromatography-mass spectroscopy) and theoretically (by DFT calculations) explored in detail. Compared to the reported literature (T. Shiraishi, T. Takano, H. Kamitakahara and F. Nakatsubo, Holzforschung, 2012, 66(3), 303–309), 1-(4-ethoxyphenyl)ethanol showed a distinguishable oxidation pathway, where the resulting carbonyl product surprisingly underwent a bond cleavage on alkyl–aryl ether to ultimately produce a quinoid like compound. In contrast, β-O-4 dimers, like 2-phenoxy-1-phenethanol and 2-phenoxyacetophenone also demonstrated electrochemical oxidation induced by Cβ–O and Cα–Cβ bond cleavages. For the oxidation products, the presence of the Cα-hydroxyl group in dimers was the key to selectively generate aldehyde-containing species under mild electrochemical conditions, otherwise it produces alcohol-containing products following a different mechanism compared to the CαO containing dimers.

Bisphenol A (BPA) is a typical endocrine-disrupting chemical. The removal of BPA has raised much concerns in recent years. This paper examined the adsorption behavior of BPA to biochars and the different effects of cationic, anionic, and nonionic surfactants. The results indicated that peanut shell biochars prepared at 300°C (BC300), 500°C (BC500), and 700°C (BC700) showed strong adsorption affinity for BPA, and the adsorption affinity of biochars increased with the increase of pyrolysis temperature. The range of log Kd values was 2.83∼3.71, 2.91∼4.57, and 3.24∼5.50 for BC300, BC500, and BC700, respectively. Both the type of surfactants and the properties of biochars could affect the adsorption behavior of BPA. Cetyltrimethyl ammonium bromide (CTAB) showed negligible effect on the adsorption of BPA on BC300, and the inhibition effect of CTAB was stronger with the increase of biochar pyrolysis temperature. Tween 20 and sodium dodecyl benzene sulfonate (SDBS) showed stronger inhibition effect than CTAB, especially on BC300. This is likely because the inhibition effect caused by competition of CTAB may be counterbalanced by the enhancement caused by the partitioning effect by adsorbed CTAB and the bridge effect between the –NH4+ group of CTAB and the phenol group on BPA/O-functional groups of biochars, whereas Tween 20 and SDBS do not have this bridge effect advantage. This study could provide insightful information for the application of biochars in removal of BPA.

Parabens are widely used as preservatives, which have been found to affect thyroid function in toxicological studies. However, population studies on whether they are associated with thyroid tumor remain unclear. This study aims to investigate the relationship between environmental paraben exposure and thyroid cancer and benign nodules. The detectable percentages of methyl paraben, ethyl paraben, and propyl paraben in the urinary samples of 425 study subjects were 99.06%, 95.29% and 92.00%, respectively. In the single pollutant model, we found statistically significant difference between certain parabens and thyroid cancer/ benign nodules. Further, we found the mixture effect of parabens on increased risk of thyroid cancer (OR = 0.24, 95% CI: 0.18, 0.31) and benign nodule (OR =1.33, 95% CI: 0.86, 1.80). The significant gender-associated effects were found in associations with certain parabens and thyroid cancer and benign nodules (Both P for interactions < 0.05). Overall, our results showed that individual exposure of paraben mixtures may be associated with the risk of thyroid cancer and benign nodules, and there were gender differences.

The ability to measure many single molecules simultaneously in larger and complex samples is critical to the translation of single-molecule sensors for practical applications in biomarker detection. The challenges lie in the limits imposed by mass transportation and thermodynamics, resulting in long assay time and/or insufficient sensitivity. Here, we report an approach called Sensing Single Molecule under MicroManipulation (SSM3) to circumvent the above limits. In SSM3, the transportation rate of analyte molecules and the kinetics of molecular interaction are fine-tuned by the nanoparticle micromanipulation. The heterogeneous lifetime of molecular complexes is quantified to discriminate specific binding from nonspecific background noise. By the highly-specific digital counting of single molecules, we demonstrate 15-minute assays for direct detection of microRNAs and amyloid-β proteins via electrical or magnetic micromanipulation, with the limit of detection at the subfemtomolar level. The presented approach could inspire more practical applications of single molecule sensors.

Stainless steel slag has been applied to other silicate materials due to its CaO-SiO2-based system. This is done to improve the utilization rate of stainless steel slag and apply it more safely. This paper investigated the occurrence of chromium in synthetic stainless steel slag containing FetO and its leaching behavior. The phase composition of the equilibrium reaction was calculated by FactSage 7.3 Equlib module. XRD, SEM-EDS and IPP 6.0 were used to investigate the phase compositions, microstructure and count the size of spinel crystals. The results indicate that the increase of Fe2O3 content can promote the precipitation of spinel phases and effectively inhibit the formation and precipitation of α-C2S in a CaO-SiO2-MgO-Cr2O3-Al2O3-FeO system. Fe2O3 contents increased from 2 wt% to 12 wt%, and the crystal size increased from 4.01 μm to 6.06 μm, with a growing rate of 51.12%. The results of SEM line scanning show the Cr-rich center and Fe-rich edge structure of the spinel phase. Comparing the TRGS 613 standard with the HJ/T 299-2007 standard, the leaching of Cr6+ in the FetO samples is far lower than the standards’ limit, and the minimum concentration is 0.00791 mg/L in 12 wt% Fe2O3 samples.

A new strategy has been developed for the direct chirality fixation, which is induced by electrochemical polymerization, of macrocyclic hosts pillar[5]arene. Taking advantage of electrochemical polymerization, thiophene-modified pillar[5]arene monomers (Th-P[5]A) have been regularly arranged under the action of an electric field to form chiral nanofiber-like crystalline pillar[5]arene-based polymers (poly-Th-P[5]A), showing a significant circular dichroism (CD) signal. With the active photochemical properties, poly-Th-P[5]A is first used as a photoelectrochemical (PEC) chiral sensor for the identification and determination of l- and d-ascorbic acid (l-AA, d-AA) without adding any extra photoactive probes. Importantly, the chiral recognition between poly-Th-P[5]A and l-AA also triggers a polarity conversion for the photocurrent of the polymer, and it greatly results in a broad chiral detection range for l-AA, crossing 6 orders of magnitude. This work provides a promotional strategy for building a PEC chiral recognition platform based on pillararenes.

BACKGROUND Bisphenols and triclosan (TCS) are common endocrine disrupters (EDCs) that may induce oxidative stress. However, there is limited information as to whether these EDCs interact with genetic variants to modify the levels of oxidative stress on a genome-wide scale. METHODS We first performed a genome-wide scan among a Chinese population and also measured three urinary EDCs, including bisphenol A (BPA), bisphenol F (BPF) and TCS, and three urinary oxidative stress markers [4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), 8-iso-prostaglandin-F2α (8-isoPGF2α) and 8-hydroxy-deoxyguanosine (8-OHdG)]. Subsequently, we examined interactions between three urinary EDCs and nearly 4.6 million genetic variants for three urinary oxidative stress markers by the general linear model. RESULTS Urinary BPA, BPF and TCS were positively associated with HNE-MA, 8-isoPGF2α and 8-OHdG. Significant rs6855040 (4p15.32/between SNORA75B and QDPR)-BPA, rs1112943 (4q35.1/SNX25)-TCS interactions were associated with the 8-isoPGF2α levels (all P

Rapid molecular diagnosis using nucleic acid biomarkers is important for timely identification of acute pathogenic infections. We introduce an active kinetic approach called sensing single molecule under micromanipulation (SSM3) to quantify nucleic acids, which circumvents hydrodynamic limits of reaction rate, sensitivity and specificity. We demonstrate the 15-minute assay to detect synthetic miRNAs with subfemtomolar limit of detection and high-confidence discrimination of single-base-pair mismatch.

Widespread iron-bearing clay minerals are potential materials that can reduce and immobilize Cr(VI) as insoluble Cr2O3/Cr(OH)3. The kinetics of this process is controlled by various environmental factors, yet the effects of such factors on Cr(VI) transformation by iron-bearing clays are poorly understood. Herein, we report the synergistic effects of reduced nontronite (rNAu-2) and environmentally prevalent organic ligands on Cr(VI) reduction under near-neutral pH conditions. The presence of ligands belonging to α-hydroxyl or carbonyl carboxylates, such as tartrate, malate, lactate, pyruvate, and mandelate, significantly promoted the rate and extent of Cr(VI) reduction by rNAu-2, likely because of the formation of Cr(V)-ligand complexes and resulting electron transfer from the ligand to Cr(V). In contrast, ligands containing carboxyl groups only, such as succinate and propionate, had a slightly inhibitory or no effect, likely because of their weak complexing ability with Cr(V) and lack of electron transfer from the ligand to Cr(V). In addition, α-hydroxyl carboxylates are probably more easily oxidized by Cr(V)/Cr(IV) than carboxylates. Soluble Cr(III)-organic complexes were the dominant products of Cr(VI) reduction in the presence of tartrate and malate. This study highlights the importance of organic ligands in the biogeochemical cycling of chromium and has significant implications for chromium remediation in contaminated environments.