Search

In the Cu/diamond composites modified by metal matrix alloying, the interfacial thermal conductance depends on the in-situ formed interfacial carbide layer that further depends on the diamond particle size. We fix boron alloying content as 0.3 wt% and vary diamond particle size from 66 to 701 µm to tune interfacial carbide layer with an attempt to separate the two dependences of diamond particle size and interfacial thermal conductance. The Cu-0.3 wt% B/diamond composite exhibits a slowing increase in thermal conductivity as the diamond particle size is larger than 300 µm because of a simultaneous decrease in the interfacial thermal conductance. A high thermal conductivity of 904 W/(m K) is obtained with diamond particle size of 701 μm. The findings emphasize the importance of tailoring interfacial carbide layer to attain high thermal conductivity in the Cu/diamond composites modified by metal matrix alloying.

In this work, zeolitic imidazolate frameworks (ZIF-8) and carboxylated carbon nanotubes (CNTs) were compounded to prepare a kebab-like one-dimensional linear composite, ZIF-8@CNTs. The mixed-matrix membrane (MMM) for separating carbon dioxide is prepared by embedding it into the polymer matrix Pebax-1657. The results indicated the successful synthesis of the ZIF-8@CNT composite. The combination of ZIF-8 and carboxylated CNTs avoided the aggregation of ZIF-8 in the polymer, increased the free volume of the MMM, and enhanced the CO2 adsorption performance and CO2/N2 separation performance. In addition, the interaction between CNTs and ZIF-8 provided a fast transport channel for CO2 molecules and improved the mechanical properties of the MMM. The 5 wt % ZIF-8@CNT MMM showed the best separation performance with a CO2 permeability of 225.5 Barrer and a CO2/N2 selectivity of 48.9, which exceeded the Robeson upper limit in 2008. The combination of high permeability and selectivity made Pebax/ZIF-8@CNT MMMs promising for industrial CO2 separation applications.

Controllable ternary Pt–Cu–Mn lamellar oxides with different amounts of Pt were synthesized using a facile and expeditious self-propagating flaming technique for catalytic oxidation of toluene. The surface structure, composition, and structure–performance relationship were investigated by combining X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, scanning electron microscopy (SEM), transmission electron microscopy (TEM), hydrogen temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectroscopy (XPS). The catalytic performance of the as-produced catalysts toward the catalytic oxidation of toluene was investigated. Among the catalysts, the 0.5Pt-MnCu catalyst has shown 90% toluene removal at 228 °C with excellent cyclic stability, which is a significant achievement for MnCu binary nanosheet-like catalysts containing low amounts of Pt (0.5 wt %). This study has also inferred the degradation activity of modulated MnCu composite catalysts, which greatly hinges on the doping level of Pt. The lattice oxygen species are dominating according to the Mn–O bond strength, local environment, and reducibility. Moreover, Pt can increase the covalency of surface metal–oxygen bonds and electron affinity of surface metal-coordinated oxygen centers, thereby expediting the adsorption/activation of the gaseous oxygen molecules on oxide surfaces, which can step up the lattice oxygen as well as oxygen vacancy-involved reactions to invoke the Mars–van Krevelen and Langmuir–Hinshelwood mechanisms for boosting the overall toluene oxidation performance of PtCuMnOx catalytic materials. Based on the obtained results, this study proposes a vital insight into manipulating the nanoscale catalytic functions, which could also promise pivotal potential toward engineering the state-of-the-art transition-metal nanostructure for environmental catalysis.

We report the synthesis of an end-to-end protein–glycopolymer conjugate, namely, site-specific modification of recombinant thrombomodulin at the C-terminus with a chain-end-functionalized glycopolymer. Thrombomodulin (TM) is an endothelial membrane glycoprotein that acts as a major cofactor in the protein C anticoagulant pathway. To closely mimic the glycoprotein structural feature of native TM, we proposed a site-specific glyco-engineering of recombinant TM with a glycopolymer. Briefly, recombinant TM containing the epidermal growth factor (EGF)-like domains 4, 5, and 6 (rTM456) and a C-terminal azidohomoalanine was modified with a dibenzylcyclooctyne (DBCO) chain-end-functionalized glycopolymer via copper-free click chemistry to afford the end-to-end TM–glycopolymer conjugate. The TM glycoconjugation was confirmed with SDS-PAGE, Western blot, and protein C activation assay, respectively. The reported site-specific end-to-end protein glycopolymer conjugation approach facilitates uniform glycoconjugate fo...

We report the synthesis, single-crystal structure, solid-state ultraviolet-visible-near-infrared spectroscopy, and theoretical calculations on the first trivalent plutonium crown ether inclusion complex, [(H3O)(18-crown-6)][Pu(H2O)4(18-crown-6)](ClO4)4·2(H2O) (denoted as PuIII-18C6). Single-crystal X-ray diffraction reveals that PuIII-18C6 crystallizes in the orthorhombic space group of Pccn, which is assembled by independent ionic pairs including [Pu(H2O)4(18-crown-6)]3+, [(H3O)(18-crown-6)]+, and perchlorate anions. The plutonium atom is fully encapsulated within the cavity of the 18-crown-6, generating a distorted bicapped square antiprism geometry. The theoretical evaluation confirms that weak Pu-O dative bond is involved between PuIII ions with 18-crown-6. This work may deepen the understanding of the host-guest interactions between trivalent transuranic and macrocyclic ligands.

This work assessed the impact of biodiesel impurities on CeO2 catalyst for soot combustion via soot-TPO experiments. The results showed that Na- and K-doped catalysts were assisted for soot combustion, while Ca- and P-doped catalysts had a negative effect. N2 adsorption-desorption and XRD results indicated that doping biodiesel impurities led to smaller surface area by blocking small pores. Surface chemical properties are suggested as major reasons for promoting soot combustion by means of XPS, H2-TPR, and O2-TPD. Na- and K-doped catalysts showed stronger redox ability and surface lattice oxygen mobility, poorly for Ca- and P-doped catalysts. Interestingly, a large number of surface oxygen species were observed on P-doped catalyst and it enhanced the ignition of bio soot. In the presence of NO, surface chemical properties including NOx storage/release capacity and NO oxidation ability were characterized by NO-adsorption DRIFTS, NO-TPO and NOx-desorption DRIFTS, alkali-doped catalyst with excellent NOx storage capacity that can release active oxygen species and gaseous NO2 accelerate heterogeneous soot combustion, and the poor NO conversion ability to NO2 that weakens the promotion effect of soot combustion. Particularly in the existence of P, the promotion effect of soot elimination in NO + O2 was further weakened by the reason of poor NOx storage capacity and NO oxidation ability.

Total synthesis of natural products has greatly contributed to natural product research, organic synthesis and drug discovery and development. However, in most cases, the efficiency of total synthesis is far from sufficient for direct practical industrial application. Thus, designing a concise and efficient synthetic route with balanced efforts between building the complex skeleton and introducing functional groups is highly desirable. In this critical review, we first present an introduction of this issue and a philosophical framework that cover possible synthetic approaches. Next, we have chosen the biogenetically closely related, biologically important and synthetically extremely challenging natural products, tiglianes, daphnanes and ingenanes as the particular case for the discussion, since in the past 40 years many synthetic approaches have been reported. The successes and pitfalls included therefore serve as the basis to draw some conclusions that may inspire future development in this area.

Two-dimensional antimonene has many potential applications for its high mobility, high stability, and tunable band gap. The covalent chemistry of antimonene and the molecular doping or hybrid of antimonene remain incomplete for further applications. In this work, silane-functionalized antimonene nanosheets and their copolymerized organically modified silicate gel glasses are designed and prepared. The experimental data confirmed that 3-glycidoxypropyltrimethoxysilane interacts covalently with antimonene. Compared with unfunctionalized antimonene, the silane-functionalized antimonene shows higher concentration, higher compatibility, and dispersion stability in solvents and gel matrices. In particular, the doping concentration of functionalized antimonene nanosheets can reach 2% in gel glass, which is larger than conventional nanocomposites and nanohybrids. These nanosheets exhibit outstanding optical limiting performance in the visible and long-wavelength near-infrared regions (532-2150 nm). The mechanism of optical limiting is found to be a combination of nonlinear absorption, nonlinear refraction, and nonlinear scattering. The silane-functionalized antimonene nanosheets and their copolymerized hybrids will be promising materials for optoelectronics, biology, energy, and others.

PTEN protein levels are regulated through ubiquitination. Here, we identify BAP1 as a deubiquitinase that physically binds to and deubiquitinates PTEN, thereby inhibiting PTEN degradation. Stabilized PTEN suppresses prostate cancer progression by inhibiting Akt phosphorylation., Deubiquitinase BAP1 is an important tumor suppressor in several malignancies, but its functions and critical substrates in prostate cancer (PCa) remain unclear. Here, we report that the mRNA and protein expression levels of BAP1 are downregulated in clinical PCa specimens. BAP1 can physically bind to and deubiquitinate PTEN, which inhibits the ubiquitination‐mediated degradation of PTEN and thus stabilizes PTEN protein. Ectopically expressed BAP1 in PCa cells increases PTEN protein level and subsequently inhibits the AKT signaling pathway, thus suppressing PCa progression. Conversely, knockdown of BAP1 in PCa cells leads to the decrease in PTEN protein level and the activation of the Akt signaling pathway, therefore promoting malignant transformation and cancer metastasis. However, these can be reversed by the re‐expression of PTEN. More importantly, we found that BAP1 protein level positively correlates with PTEN in a substantial fraction of human cancers. These findings demonstrate that BAP1 is an important deubiquitinase of PTEN for its stability and the BAP1‐PTEN signaling axis plays a crucial role in tumor suppression.

The potential applications of metal-organic cages (MOCs) are mostly achieved through specific host-guest interactions within their cavities. Electronic applications would require an effective electron transport pathway, which has been extensively studied in hybrid organic-inorganic materials with extended structures. These properties have not been considered for MOCs because cage-to-cage interactions in these materials have rarely been examined and are challenging to functionalize. We report here a previously unobserved actinide-based MOC assembled from four hexagonal-bipyramidal-coordinated uranyl ions and six bidentate flexible ligands. Remarkably, each isolated cage is further interlocked with six adjacent ones through mechanical bonds, resulting in the first case of a 0D → 3D f-element polycatenated metal-organic cage

Crystalline coordination complexes of actinides, especially in atypical oxidation states, are not only fundamentally important for expanding the notably limited knowledge on the bonding nature of a...

This study was designed to investigate the anti-inflammatory, analgesic activity of azadirone from Toona sinensis (Juss.) M. Roem., Meliaceae, and explore its potential mechanisms. Anti-inflammatory activities of azadirone were evaluated using dimethylbenzene-induced ear edema, acetic acid–induced vascular permeability, and cotton ball granuloma in mice; in addition, its analgesic activities were investigated using acetic acid writhing, hot plate pain, and formalin pain tests. The results showed that azadirone had obvious anti-inflammatory and analgesic effects in animals. Further studies revealed that azadirone can reduce levels of TNF-α, IL-6, and IL-1 in lipopolysaccharide-stimulated RAW 264.7 cells. In addition, azadirone can downregulate COX-2 and substance P in spinal cord tissues of formalin-stimulated mice. Also, expressions of ERK, P38, and JNK in RAW 264.7 cells were suppressed by azadirone. Collectively, azadirone has promising anti-inflammatory and analgesic potentials, and its mechanism is closely related to the reduction of pro-inflammatory cytokines and the blocking of MAPK signal pathway.

LIN28A is a conserved RNA‐binding protein that inhibits the biogenesis of let‐7 microRNAs, thus promoting cancer progression. However, mechanisms underlying the activation of the LIN28A‐let‐7 signaling pathway remain poorly understood. Here, we show that LIN28A is SUMOylated in vivo and in vitro at K15, which is increased by hypoxia but reduced by chemotherapy drugs such as Cisplatin and Paclitaxel. SUMOylation of LIN28A aggravates its inhibition of let‐7 maturation, resulting in a stark reduction in let‐7, which promotes cancer cell proliferation, migration, invasion, and tumor growth in vivo. Mechanistically, SUMOylation of LIN28A increases its binding affinity with the precursor let‐7 (pre‐let‐7), which subsequently enhances LIN28A‐mediated recruitment of terminal uridylyltransferase TUT4 and simultaneously blocks DICER processing of pre‐let‐7, thereby reducing mature let‐7 production. These effects are abolished in SUMOylation‐deficient mutant LIN28A‐K15R. In summary, these findings shed light on a novel mechanism by which SUMOylation could regulate the LIN28A‐let‐7 pathway in response to cellular stress in cancer cells., This study demonstrated that SUMOylation of LIN28A increases the binding affinity of LIN28A with pre‐let‐7, subsequently to promote TUT4‐mediated uridylation and block DICER processing of pre‐let‐7, thus leading to the reduction of mature let‐7. SUMOylation of Lin28A is regulated in response to cancer cellular stresses such as hypoxia and chemotherapy drug treatment, which have implications in cancer prognosis and therapy.

Uric acid crystal is known to activate the NLRP3 inflammasome and to cause tissue damages, which can result in many diseases, such as gout, chronic renal injury and myocardial damage. Meanwhile, soluble uric acid (sUA), before forming crystals, is also related to these diseases. This study was carried out to investigate whether sUA could also activate NLRP3 inflammasome in cardiomyocytes and to analyse the mechanisms. The cardiomyocyte activity was monitored, along with the levels of mature IL‐1β and caspase‐1 from H9c2 cells following sUA stimulus. We found that sUA was able to activate NLRP3 inflammasome, which was responsible for H9c2 cell apoptosis induced by sUA. By elevating TLR6 levels and then activating NF‐κB/p65 signal pathway, sUA promoted NLRP3, pro‐caspase 1 and pro‐IL‐1β production and provided the first signal of NLRP3 inflammasome activation. Meanwhile, ROS production regulated by UCP2 levels also contributed to NLRP3 inflammasome assembly and subsequent caspase 1 activation and mature IL‐1β secretion. In addition, the tlr6 knockdown rats suffering from hyperuricemia showed the lower level of IL‐1β and an ameliorative cardiac function. These findings suggest that sUA activates NLRP3 inflammasome in cardiomyocytes and they may provide one therapeutic strategy for myocardial damage induced by sUA.

To settle the realization difficulty of continuous rotating detonation (CRD) fueled by hydrocarbon, a cavity-based annular combustor scheme was proposed in our previous study, and its feasibility w...

Diamond particles reinforced boron-alloyed Cu matrix (Cu-xB/diamond, x = 0.1, 0.2, 0.3, 0.4, 0.5, and 1.0 wt.%) composites were prepared by gas pressure infiltration. The size of the diamond particles was ~ 230 μm and the diamond volume fraction in the composites was ~ 66%. The interfacial carbide evolution plays an important role in improving the interfacial bonding and enhancing the mechanical properties of the Cu-B/diamond composites. The tensile, compressive and bending strengths firstly increase and then decrease with increasing boron content, giving a maximum tensile strength of 204 MPa, a maximum compressive strength of 608 MPa, and a maximum bending strength of 513 MPa at 0.5 wt.% B addition. The monotonic uniaxial tensile stress–strain curves of the Cu-B/diamond composites were predicted by using the Mori–Tanaka, generalized self-consistent, and Torquato identical hard spheres approximation models. The results suggest that alloying B to Cu matrix is an effective route to strengthening Cu/diamond composites.

Tiglianes such as prostratin and related diterpenoids are biologically significant natural molecules and long-standing targets for organic synthesis community. Due to the complex polycyclic scaffolds, high oxygenation level, and dense functional groups and stereocenters, their de novo chemical syntheses still face formidable challenges despite extensive efforts in the past 40 years. This account details the development of a modular and concise synthesis of prostratin, a potent anti-HIV and anticancer agent. The key approach in this synthesis involved a sequence of oxidative dearomatization and sequential stereoselective installation of peripheral groups to rapidly build the contiguously substituted cyclohexane C-ring. Inspired by Wender's work, an acid- and solvent-controlled stereodivergent formation of cyclopropane D-ring was developed. Mechanistic investigations by computational methods revealed that the competition between intra- and intermolecular hydrogen bonding led to different conformations, thus favoring different protonation processes. The designed and unexpected chemistry along this campaign reflected the uniqueness of the natural structures and should be amenable to future chemical syntheses of related complex polycyclic molecules.

The increased demand for more efficient, safe, and green production in fine chemical and pharmaceutical industry calls for the development of continuous-flow manufacturing, and for chiral chemicals in particular, enantioselective catalytic processes. In recent years, this emerging direction has received considerable attention and has seen rapid progress. In most cases, catalytic enantioselective flow processes using homogeneous, heterogeneous, or enzymatic catalysts have shown significant advantages over the conventional batch mode, such as shortened reaction times, lower catalysts loadings, and higher selectivities in addition to the normal merits of non-enantioselective flow operations. In this Minireview, the advancements, key strategies, methods, and technologies developed the last six years as well as remaining challenges are summarized.

Numerous studies have reported that c-Src is highly expressed with high tyrosine kinase activity in a variety of tumors. However, it remains unclear whether c-Src contributes to the miRNA pathway. Here, we report that c-Src can interact with and phosphorylate AGO2, a core component of RISC complex, at tyr 393, tyr 529 and tyr749. Mechanistically, it is confirmed that c-Src phosphorylation of AGO2 at tyr393 reduces its binding to DICER, thereby suppressing the maturation of long-loop pre-miR-192. However, the other two phosphorylation sites don’t work on this function. Significantly, Ectopic expression of wild-type AGO2, but not the three tyrosine site mutants, has an obvious tumor-promoting effect in vitro and in vivo, which function could be blocked thoroughly by treatment with c-Src kinase inhibitor, Saracatinib. Our findings identify AGO2 as c-Src target and c-Src phosphorylation of AGO2 may therefore play a potential role during tumor progress. Keywords: c-Src, AGO2, Tyrosine phosphorylation, Tumorigenesis, Saracatinib

Continuous Rotating Detonation (CRD) is a promising combustion mode for aerospace propulsion, with high heat release rate and thermodynamic efficiency, but it exhibits realization difficulty for fuels with low chemical activity. To settle this issue, a cavity-based annular combustor scheme has been proposed in our previous study, and its feasibility has been well demonstrated. A series of ethylene-air tests under different cavity configurations have been carried out in this paper, and the effects of cavity depth are revealed. For CRD mode, traditional isobaric combustion also exists at the contact surface between the high temperature burnt products and combustible mixture. Increasing the cavity depth can improve its isobaric combustion holding ability, but excessive isobaric combustion could destroy the foundation of CRD. For fuels with low chemical activity, appropriately improving the isobaric combustion can help the CRD realization. This paper reveals the cavity depth effects on the competitive relationship between isobaric combustion and CRD, and it can be used as a guideline for the CRD combustor design.

The universal [5-7-6] tricyclic framework of tigliane and daphnane diterpenes containing five contiguous stereocenters has been synthesized in 9 steps from readily available starting materials in a completely stereocontrolled manner. This was enabled by designing a semi-flow tube-based bubbling photoreaction setup for an efficient oxidative dearomatization and by devising an open chain remote group-assisted selective 1,4-addition. The results provide a potentially rapid and divergent approach to synthesize various related diterpene molecules.

In response to the increasing desire for modern industries to be both green and sustainable, there has been increasing research focus on the reutilization of natural waste materials to effectively remove and degrade toxic wastewater effluents. One interesting food industry waste product is clam shells. Here a new photocatalytic nanomaterial derived from marine clam shells was successfully prepared and characterized. Thereafter the material was applied for the removal of two target dyes from aqueous solution, where the effect of both catalyst dose and initial dye concentration on adsorption and photocatalysis properties was investigated. The maximum adsorption capacities of methylene blue (100 mg/L) and Congo red (500 mg/L) were 123.45 mg/g and 679.91 mg/g, respectively, where adsorption followed pseudo second order kinetics predominantly via a chemical adsorption process. The photodegradation removal efficiencies of the two dye solutions under visible light irradiation were 99.6% and 83.3% for MB and CR respectively. These results demonstrated that a clam shell catalyst also exhibited excellent degradation performance in a mixed dye solution with strong degradation capability and low cost, making the material a good candidate for practical field remediation of dye contaminated wastewater.

A simple, economical, and efficient method for fabricating stable hydrophilic/underwater superoleophobic coating under harsh conditions remains a significant challenge. Here, by the hydrolysis of 3-(Methacryloyloxy) propyltrimethoxysilane (TMSPMA) on cotton fabric and the free radical polymerization of [2-(Methacryloyloxy) ethyl] dimethyl-(3-sulfonic acid propyl) ammonium hydroxide (SBMA) and TMSPMA, a superhydrophilic coating was fabricated. The coating can withstand harsh environments, such as strong acid and alkali. In addition, the coated cotton fabrics show an effective separation of surfactant-stabilized oil-in-water emulsions with extreme flux as high as 1500 Lm−2 h−1 only under gravity. Importantly, the oil-contaminated coated cotton fabrics can be cleaned only by water washing. The outstanding properties of the coating including durability, recyclability and resistance to harsh environment, highlight its practical application in emulsion separation and oily wastewater purification. Keywords: Coating, Superhydrophilicity, Underwater superoleophobicity, Harsh environment

Hypoxia is the most prominent feature in human solid tumors and induces activation of hypoxia-inducible factors and their downstream genes to promote cancer progression. However, whether and how hypoxia regulates overall mRNA homeostasis is unclear. Here we show that hypoxia inhibits global-mRNA decay in cancer cells. Mechanistically, hypoxia induces the interaction of AGO2 with LUBAC, the linear ubiquitin chain assembly complex, which co-localizes with miRNA-induced silencing complex and in turn catalyzes AGO2 occurring Met1-linked linear ubiquitination (M1-Ubi). A series of biochemical experiments reveal that M1-Ubi of AGO2 restrains miRNA-mediated gene silencing. Moreover, combination analyses of the AGO2-associated mRNA transcriptome by RIP-Seq and the mRNA transcriptome by RNA-Seq confirm that AGO2 M1-Ubi interferes miRNA-targeted mRNA recruiting to AGO2, and thereby facilitates accumulation of global mRNAs. By this mechanism, short-term hypoxia may protect overall mRNAs and enhances stress tolerance, whereas long-term hypoxia in tumor cells results in seriously changing the entire gene expression profile to drive cell malignant evolution.

Ocean-related global change has strongly affected the competition between key marine phytoplankton groups, such as diatoms and dinoflagellates, especially with the deleterious consequency of the increasing occurrence of harmful algal blooms. The dominance of diatoms generally shifts toward that of dinoflagellates in response to increasing temperature and reduced nutrient availability; however, contradictory findings have also been observed in certain sea areas. A key challenge in ecology and biogeochemistry is to quantitatively determine the effects of multiple environmental factors on the diatom-dinoflagellate community and the related changes in elemental and biochemical composition. Here, we test the interplay between temperature, nutrient concentrations and their ratios on marine diatom-dinoflagellate competition and chemical composition using bi-algal competition experiments. The ubiquitous diatom Phaeodactylum tricornutum and dinoflagellate Prorocentrum minimum were cultivated semi-continuously, provided with different N and P concentrations (three different levels) and ratios (10:1, 24:1, and 63:1 molar ratios) under three temperatures (12, 18, and 24°C). The responses of diatom-dinoflagellate competition were analyzed by a Lotka-Volterra model and quantified by generalized linear mixed models (GLMMs) and generalized additive models (GAMs). The changes in nutrient concentrations significantly affected diatom-dinoflagellate competition, causing a competitive superiority of the diatoms at high nutrient concentrations, independent of temperature and N:P supply ratios. Interestingly, the effect amplitude of nutrient concentrations varied with different temperatures, showing a switch back toward a competitive superiority of the dinoflagellates at the highest temperature and at very high nutrient concentrations. The ratios of particulate organic nitrogen to phosphorus showed significant negative correlations with increasing diatoms/dinoflagellates ratios, while lipid biomarkers (fatty acids and sterols) correlated positively with increasing diatoms/dinoflagellates ratios over the entire ranges of temperature, N and P concentrations and N:P ratios. Our results indicate that the integration of phytoplankton community structure and chemical composition provides an important step forward to quantitatively understand and predict how phytoplankton community changes affect ecosystem functions and biogeochemical cycles in the ocean.

Fe(III) coagulation-precipitation process has been widely used to remove heavy metals from industrial effluents; however, the influences of organic ligands on the sequestration of different heavy metals in the Fe(III)/metal-EDTA ternary system are not well understood. In this study, the pH-dependent mechanisms of CuII-EDTA and NiII-EDTA removed by in-situ formed iron (oxy)hydroxides were studied using surface complex modeling and a suite of characterization techniques. Results of surface complex model indicated that there should be minimal difference between removal of CuII-EDTA and NiII-EDTA by iron (oxy)hydroxides if adsorption was the dominant mechanism. However, through the speciation analysis and characterization of the precipitates generated after coagulation and precipitation, we have demonstrated that at neutral pH the complexation of Fe(III) and EDTA influenced the surface properties of iron (oxy)hydroxides formed, with the higher removal of Cu2+ (compared to Ni2+) contributed by its coprecipitation with Fe(III). Moreover, at basic pH, decomplexation of CuII-EDTA occurred on the iron (oxy)hydroxides surface with the released copper ions involved in the formation of (oxy)hydroxides. The low removal of nickel (from NiII-EDTA) was ascribed to the higher conditional stability constant of NiII-EDTA. Results of this study have advanced our understanding of the complicated interactions among Fe(III), organic ligands and heavy metals in the industrial effluents, and provide insight to optimization of the process efficiency.

Long non-coding RNAs (lncRNAs) are a kind of non-coding RNAs which may play vital roles in bacterial infection induced cardiomyocytes injury. We aim to investigated the roles of lncRNA DLX6-AS1 in LPS-induced human AC16 cardiomyocytes apoptosis and investigate the corresponding mechanisms in this study. The expression of DLX6-AS1 in LPS-injured human AC16 cardiomyocytes was detected by RT-PCR. The functions of DLX6-AS1 and miR-497 on AC16 cells apoptosis and viability were studied using flow cytometry, Caspase 3 activity analysis, and CCK8 assay. DLX6-AS1 was upregulated in LPS-induced human AC16 cardiomyocytes and the high-level DLX6-AS1 accelerated apoptosis and restrained viability of LPS-injured AC16 cells. MiR-497 was a target of DLX6-AS1. DLX6-AS1 mediates apoptosis of LPS-induced AC16 cardiomyocytes injury via miR-497. DLX6-AS1/miR-497 regulated endoplasmic reticulum (ER) stress‑associated apoptosis via regulating Calcium-sensing Receptor (CaSR). DLX6-AS1 was upregulated in LPS-induced human AC16 cardiomyocytes and involved in the LPS-induced AC16 cells apoptosis via facilitating ER stress by modulating miR-497/CaSR signaling pathway.

Aberrant activity of polycomb repressive complex 2 (PRC2) is involved in a wide range of human cancer progression. The WD40 repeat-containing protein EED is a core component of PRC2 and enhances PRC2 activity through interaction with H3K27me3. In this study, we report the discovery of a class of pyrimidone compounds, represented by BR-001, as potent allosteric inhibitors of PRC2. X-ray co-crystallography showed that BR-001 directly binds EED in the H3K27me3-binding pocket. BR-001 displayed antitumor potency in vitro and in vivo. In Karpas422 and Pfeiffer xenograft mouse models, twice daily oral dosing with BR-001 resulted in robust antitumor activity. BR-001 was also efficacious in syngeneic CT26 colon tumor-bearing mice; oral dosing of 30 mg/kg of BR-001 led to 59.3% tumor growth suppression and increased frequency of effector CD8+ T-cell infiltrates in tumors. Pharmacodynamic analysis revealed that CXCL10 was highly upregulated, suggesting that CXCL10 triggers the trafficking of CD8+ T cells toward tumor sites. Our results demonstrate for the first time that inhibition of EED modulates the tumor immune microenvironment to induce regression of colon tumors and therefore has the potential to be used in combination with immune-oncology therapy. Significance: BR-001, a potent inhibitor of the EED subunit of the PRC2 complex, suppresses tumor progression by modulating the tumor microenvironment.

Thermally conductive yet electrically insulating two-dimensional boron nitride nanosheets (BNNSs) have been an ideal choice for the enhanced fillers for improving thermal properties of polymer-based composites. As a nanofiller with an ultrahigh aspect ratio, BNNSs result in conspicuous stacking along the planar direction in the preparation of composites, which results in strong anisotropy of heat transfer and suppresses out-plane thermal dissipation. Thus, it is necessary to facilitate the out-plane heat transfer by building a favorable microstructure. Focusing on the structural design of the nanofiller itself here, we have fabricated a novel three-dimensional nanofiller with improved out-plane connections. Carbon nanotubes (CNTs) have been grown in situ on the surface of BNNSs using chemical vapor deposition. Utilizing these sandwich-like nanostructure BNNSs/CNTs as fillers in the composites, we have assembled diverse sorts of composites, such as flexible films, scleroid 3D mats, painted ink, and viscous grease. Simultaneously, their thermal and insulating properties have been evaluated. A nearly 330% enhancement of out-plane thermal conductivity from the control sample filled with pristine BNNS is achieved, and the composite also exhibits good electrical resistivity of above 7.5 × 10

The design and synthesis of uranium sorbent materials with high uptake efficiency, capacity and selectivity, as well as excellent hydrolytic stability and radiation resistance remains a challenge. Herein, a polyoxometalate (POM)-organic framework material (SCU-19) with a rare inclined polycatenation structure was designed, synthesized through a solvothermal method, and tested for uranium separation. Under dark conditions, SCU-19 can efficiently capture uranium through ligand complexation using its exposed oxo atoms and partial chemical reduction from UVI to UIV by the low-valent Mo atoms in the POM. An additional UVI photocatalytic reduction mechanism can occur under visible light irradiation, leading to a higher uranium removal without saturation and faster sorption kinetics. SCU-19 is the only uranium sorbent material with three distinct sorption mechanisms, as further demonstrated by X-ray photoelectron spectroscopy (XPS) and X-ray absorption near edge structure (XANES) analysis.

Aluminum matrix composites with nondirectional graphite-flake reinforcement were fabricated by hot-press sintering. To avoid interfacial reactions in the graphite-flake-reinforced composites, copper (Cu), with a thickness of approximately 50 μm, was coated on the graphite flakes by chemical plating. The results show that the Cu is uniformly distributed on the surface of graphite flakes. The thickness of the Cu plating is in the range of 15.3–21.2 μm. For volume fractions of the nondirectional graphite flakes ranging from 40% to 70%, the Al/Cu-plated graphite-flake (Cu-GF) composites display thermal conductivities from 328 W/m K to 612 W/m K. The theoretical values calculated by the parallel alternate layer model are slightly higher than the experimental values. The friction coefficient (0.171) and wear rate (2.31 × 10−7 mm3/N mm) of the composites with 70% Cu-plated graphite flakes are the lowest of the compositions observed in this study. Owing to the lubrication of graphite, the friction coefficient and wear rate decrease with increasing graphite flake content. The thermal conductivity and wear resistance gradually increase when the volume fraction of the Cu-plated graphite flake increase.

Csk, a non-receptor tyrosine kinase, serves as an indispensable negative regulator of the Src family kinases (SFKs). However, little is known about regulation of Csk expression so far. SUMOylation, a reversible post-translational modification, has been shown to regulate many biological processes especially in tumor progression. Here we report that Csk is covalently modified by SUMO1 at lysine 53 (K53) both in vitro and in vivo. Treatment with hydrogen peroxide inhibited this modification to a certain extent, but PIAS3, identified as the main specific SUMO E3 ligase for Csk, could significantly enhance SUMO1-Csk level. In addition, phosphorylation at Ser364, the active site in Csk, had no effect on this modification. Ectopic expression of SUMO-defective mutant, Csk K53R, inhibited tumor cell growth more potentially than Csk wild-type. Consistent with the biological phenotype, the SUMO modification of Csk impaired its activity to interact with Cbp (Csk binding protein) leading to decreased c-Src phosphorylation at Y527. Our results suggest that SUMOylation of Csk mainly at lysine 53 negatively modulates its tumor suppressor function by reducing its binding with Cbp and consequently, inducing c-Src activation.

Cu-B matrix composites reinforced with diamond particles (Cu-B/diamond) were prepared by gas pressure infiltration (GPI). The effect of boron addition in the range of 0–1.0 wt% on the thermal expansion behavior of the Cu-B/diamond composites was evaluated. The coefficient of thermal expansion (CTE) of the Cu-B/diamond composites initially decreases and then increases with increasing boron content. The minimum CTE value of 4.88 × 10−6/K is obtained at 0.5 wt% B addition, which satisfies the requirement of CTE of semiconductors (range of 4–8 × 10−6/K) for electronic packaging applications. The variation of CTE of the Cu-B/diamond composites is attributed to the formation of interfacial carbides and their morphological evolution. The interface structure evolves from discrete triangular carbides into continuous carbide layer with increasing boron content. The increase in the quantity of discrete carbides enhances the interface, but the formation of continuous carbides impairs the interfacial bonding of the Cu-B/diamond composites. The results suggest that alloying B to Cu matrix is an effective route to tune the coefficient of thermal expansion of Cu/diamond composites.

Diamond particles reinforced Cu matrix (Cu/diamond) composites were prepared by alloying 0.1–1.0 wt% B to the Cu matrix in order to tailor the interface structure. The interface structure evolves from discrete triangular carbides into continuous jig-saw carbides depending on the availability of boron source in the Cu-B matrix. We report the highest thermal conductivity of 868 W/mK so far in boron-modified Cu/diamond composites, which originates from the discontinuous carbide interface in the Cu-B/diamond composites. The parallel connection of interfacial thermal resistances of the discontinuous carbide interface reduces the total interfacial thermal resistance and therefore promotes phonon transfer across the Cu/diamond interface. We clarify the formation mechanism of discontinuous carbide interface in the Cu-B/diamond composites and demonstrate the decisive role of discrete triangular carbides in enhancing thermal conductivity of Cu/diamond composites. The results help to establish the method of metal matrix alloying to prepare Cu/diamond composites with high thermal conductivity for thermal management applications.

The ocean’s biological pump strongly influences atmospheric CO2 and regulates Earth’s climate. Determining the contribution of different phytoplankton groups to the biological pump over geological timescales remains an important, yet elusive, goal in biogeochemistry and organic geochemistry. Towards that end, source-specific lipid biomarkers can be used, but this approach requires the quantification of the biomarker-to-carbon ratio in different phytoplankton species, and under differing environmental conditions. We investigated responses of brassicasterol, dinosterol and C37 alkenones to three temperatures (15, 20 and 25 °C) and three N:P supply ratios (10:1, 24:1 and 63:1 mol mol−1) in three diatoms, three dinoflagellates and one coccolithophore, in laboratory experiments. Brassicasterol was produced by one diatom species, three dinoflagellates and the coccolithophore Emiliania huxleyi, while dinosterol and C37 alkenones were produced by dinoflagellates and E. huxleyi, respectively. Overall, carbon-normalized contents of lipid biomarkers varied by about a factor of three over the wide ranges of temperature and N:P supply ratios, in all species. Within the factor of three, brassicasterol was highest under the balanced N:P condition in diatoms, but under N and P deficiency in dinoflagellates. Brassicasterol in E. huxleyi was highest at lower temperatures. Dinosterol in dinoflagellates and C37 alkenones in E. huxleyi varied with temperature and N:P supply ratios, but not systematically. Compared to those in our experiments, smaller ranges are expected of N:P ratios and temperature and hence carbon-normalized biomarker contents at individual locations over time. Thus, our results imply that lipid biomarkers can be used to estimate taxon-specific carbon fluxes through time.

The aim of the present work is to investigate and compare the non-catalytic and catalytic reactivities of real and model soot samples through temperature-programmed oxidation (TPO). Such reactivity was furthermore correlated with soot structural properties, determined by laser granulometry, XRD, Raman and HRTEM. Biodiesel soot samples were obtained through the combustion of different fuels in a real engine, whereas model soot samples were produced in a laminar burner. TPO evidenced that the soot generated with 100% Biodiesel (methyl ester) was more reactive than real soot generated with 7% Biodiesel (7% methyl ester). The model soot from the diesel surrogate (Aref) containing 7% oxygenate additive (C11H22O2) exhibited higher reactivity than the model soot containing 30% additive, whereas a carbon black (Degussa Printex U) showed the poorest reactivity of this series. The presence of NO2 promoted the non-catalytic oxidation of real soot. In the presence of the MnOx-CeO2 catalyst, soot reactivity depended both on reactant gas composition and on soot-catalyst contact.

TixNb1-xN coatings have been deposited onto silicon substrates using reactive DC co-sputtering of titanium and niobium targets. The coatings range in composition from TiN to NbN with mixtures taking the general form of TixNb1-xN. Using standard materials characterisation techniques (SEM, AFM, EDS, GA-XRD), the films have been assessed for their deposition rate, grain size, surface roughness, composition and structure as a function of applied Ti/Nb discharge power. This preliminary investigation has shown that the basic characteristics of these coatings tend to display a consistent trend with the applied discharge power. This provides a convenient method for deposition control. It has also been identified that the respective sensitivity to nitrogen poisoning by the Ti and Nb targets is an important point of consideration during processing. Further investigations are needed to gain a more complete understanding of how TixNb1-xN coatings may be deposited to achieve optimized performance under orthopaedic applications. The present investigation is considered the first dedicated attempt to acquire such control.

TiNbN coatings are being applied to orthopaedic hip and knee implants for the purpose of improved wear resistance and reduced friction during application. However, the performance of these coatings is not always satisfactory and improvements in reliability in particular, are needed. Fundamentally, this stems from a lack of materials processing knowledge. In the present investigation, TixNbyNz coatings have been processed using reactive magnetron sputtering. The aim has been to establish the fundamental relationships that exist between several common sputtering parameters and the material properties exhibited by the resulting coatings. The sputtering parameters include deposition pressure, nitrogen partial pressure, applied substrate heating, and applied substrate bias, and the materials properties include composition, structure, microstructure and surface roughness. The present investigation is the second of a two component investigation on the processing of TixNbyNz coatings.

Natural and human-induced hydrological changes can influence organic carbon (OC) composition in fluvial systems, with biogeochemical consequences in both terrestrial and marine environments. Here, we use bulk and molecular carbon isotopes (13C and 14C) to examine spatiotemporal variations in particulate OC (POC) composition and age from two locations along the course of the Yellow River during 2015 and 2016. Dual carbon isotopes enable deconvolution of modern, pre-aged (millennial age) soil, and fossil inputs, revealing heterogeneous OC sources at both sites. Pre-aged OC predominated at the upstream site (Huayuankou) throughout the study period, mostly reflecting the upper riverine OC. Strong downstream (Kenli) intra-annual variations in modern and pre-aged OC were caused by increased contributions from modern aquatic OC production under the drier and less turbid conditions during this El Nino year. The month of July, which included the human-induced water and sediment regulation (WSR) event at Kenli, accounted for 82% of annual POC flux, with lower modern OC contribution compared with periods of natural seasonal variability. Both natural and human-induced hydrological events clearly exert strong influence on both fluxes and composition of Yellow River POC which, in turn, affect the balance between OC remineralization and burial for this major fluvial system.