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Tumor microenvironment-activated prodrugs have emerged as a promising strategy in precision medicine. However, the endogenous stimuli in the tumor microenvironment are often insufficient and unevenly distributed, impeding efficient and rapid prodrug conversion, necessitating the incorporation of complementary therapeutic strategies to amply treatment effectiveness. This study presents a self-synergistic therapeutic approach that combines hypoxia-activated paclitaxel prodrug (pro-PTX) with near-infrared-II (NIR-II) light-triggered photothermal therapy (PTT) for boosted tumor treatment. Initially, an organic polymer with strong NIR-II light harvesting capability, efficient photo-to-heat conversion, and excellent photostability was meticulously synthesized by introducing electron-withdrawing trifluoromethyl substituent. The high-performance NIR-II photothermal polymer then served as the matrix to encapsulate the hypoxia-responsive pro-PTX prodrug, forming the nanocore, on which the cell membrane derived from natural killer (NK) cells was further cloaked. The biomimetic nanopaltform exhibited a superior affinity towards tumor cells compared to normal cells, owing to the inherent tumor-recognition capability of NK cell membrane proteins. Upon exposure to NIR-II laser, the photothermal agent induced localized hyperthermia, facilitating not only direct tumor eradication but also exacerbating hypoxia within the tumor microenvironment. This, in turn, expedited the release of hypoxia-responsive prodrugs. Consequently, the synergistic effect of NIR-II PTT and chemotherapy efficiently induced cancer cell apoptosis and inhibited tumor growth. The developed nanoplatform, integrating hypoxia-responsive prodrug, high-performance NIR-II PTT agent-mediated complementary phototherapy, and NK cell-inspired active targeting, represents a promising strategy for precise and boosted tumor treatment. [Display omitted] • A nanoplatform integrates hypoxia-responsive prodrug, NIR-II PTT phototherapy, and NK cell-inspired active targeting. • Photothermal tumor ablation disrupted blood flow, creating severe hypoxia and expediting prodrug release. • NIR-II PTT and prodrug combo enhanced cancer cell apoptosis, suppressed tumor growth, and reduced pulmonary metastasis. [ABSTRACT FROM AUTHOR]

• Evaporation kinetics of droplet on two-tier hierarchical micro-pillar array surfaces are systematically studied. • Droplet evaporation on two-tier surface is superior to single-tier competitor when secondary pillars are on primary pillar sides or on substrate parallel to primary. • Droplet evaporation is deteriorated when secondary pillars are on primary pillar top due to liquid layer wrapped around primary pillar by capillary wicking. • Evaporation on surface with secondary pillars on substrate parallel to primary is dominated by triple-phase contact line on secondary pillars. • Geometrical effects of primary pillar including pillar side length, spacing and height and mechanisms are analyzed. As surface modification becomes a promising approach to thermal management, quantifying effects of surface structure geometrical dimension is of great significance to optimize heat transfer performance. In this paper, we emphatically report droplet evaporation on three types of two-tier hierarchical micro-pillar array (THM) surfaces. Utilizing the lattice Boltzmann model, evaporation characteristics including droplet morphology, triple-phase contact line (TPCL) behavior, liquid–vapor interface evolution and heat flux distribution are elucidated. In comparison to single-tier micro-pillar array (SM) surfaces, THM surfaces enable remarkable enhancement in heat transfer when secondary pillars are configured on the side of the primary pillar or configured parallelly to the primary pillar on the substrate, which is attributed to the synergistic effect of TPCL evaporation and liquid–vapor interface evaporation. The varying trend of droplet lifetime with the primary pillar geometrical dimension on all THM surfaces are also summarized, giving a guideline for optimization of heat dissipation by tailoring structures. [ABSTRACT FROM AUTHOR]

Varicella zoster virus (VZV) and its re-emergence as herpes zoster (HZ) is associated with significant morbidity and mortality. While studies show that VZV vaccination is effective in reducing VZV incidence, many decision makers have not added VZV to their vaccination schedule, largely due to uncertainty surrounding the effect of VZV vaccination on HZ incidence (exogenous boosting, EB), and the cost-effectiveness (CE) of vaccination. A systematic review was conducted to identify the current published evidence of CE of VZV vaccination strategies where both VZV and HZ incidence were modelled. Six studies (one published in 2003 and five between 2010 and 2019), were identified with all conducting cost-utility analysis using a dynamic transmission modelling approach and assuming EB. All predicted that mass infant VZV vaccination would rapidly reduce VZV incidence, but HZ incidence would increase. Compared with no-vaccination, the CE of VZV vaccination strategies ranged from higher costs and poorer outcomes (dominated), towards CE (incremental cost-effectiveness ratios of between $7,000 to $61,000 USD), or lower cost and better outcomes (dominant). However, without EB, HZ incidence immediately dropped below pre-vaccination levels making VZV vaccination quickly CE and/or dominant to a no vaccination strategy. Current models are sensitive to assumptions of EB suggesting that future studies consider an agent-based modelling approach to address the individual nature of variables that determine the infectiousness of VZV. [ABSTRACT FROM AUTHOR]

• Three-dimensional symmetric phase-change lattice Boltzmann model is built up to investigate sessile droplet boiling on micro-pillar array surface in the nucleate boiling regime. • Effects of micro-pillar size on bubble evolution behaviors accompanied with droplet boiling morphologies, manifested in bubble nucleation, growth, coalescence and rupture are studied. • Quantitatively assessed include nucleation activation time, droplet total evaporation time, isolated bubble nuclei density, bubble size and substrate heat flux. • Temperature, confined space and fluid flow are discussed as key factors affecting the preferential activation location and the distribution of nucleation sites. • Understanding of droplet/bubble two-phase dynamics gives some insights to optimizing droplet nucleate boiling heat transfer performance by manipulating surface properties. Despite spray cooling in the form of droplet boiling on a textured surface being a very promising phase-change heat dissipating method, the understanding of droplet/bubble two-phase dynamics in the nucleate boiling is extraordinarily limited. In this study, we report sessile droplet boiling on micro-pillar array surface in the nucleate boiling regime using a three-dimensional lattice Boltzmann model comprehensively. Effects of micro-pillar size on bubble behaviors inside droplet are discussed in detail, covering bubble nucleation, growth, coalescence, and rupture. For the micro-pillars with large side length or small spacing, nucleation sites are activated around micro-pillar top surface. The preferential activation location of nucleation sites is determined by temperature, confined space and fluid flow. In bubble growth stage, the variation of bubble radius with time follows the square root law, being consistent with previous experiments. Bubbles merge into a large central bubble beneath droplet for the short micro-pillars while into a vapor layer for the long micro-pillars. Emergence of large central bubble prolongs droplet lifetime but deteriorates heat transfer. In addition, increasing micro-pillar side length or decreasing micro-pillar height can delay activation of nucleation sites. [ABSTRACT FROM AUTHOR]

Crystalline poly ether ether ketone (PEEK) is an emergent effective sizing agent for carbon fiber (CF) for use in CF/PEEK composites. Soluble PEEK with the ability to recover crystallinity via simple acidification was synthesized and grafted on carbon nanotube for the first time to enhance the effectiveness and thermomechanical integrity of the based sizing, to achieve a higher level of chemical resistance and interfacial enhancement. CNT-filled, acidified-CNT-filled, and PEEK-grafted-CNT-filled sizing compounds were synthesized and coated on to CF. Proton nuclear magnetic resonance (1H NMR) and Fourier-transform infrared (FTIR) spectroscopy were used to analyze the products of chemical synthesis, whereas X-ray photoelectron spectroscopy (XPS) was used to assess the grafting reaction. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to assess the morphology of the unsized and sized CF, and a microbond test was used to evaluate the interfacial shear strength (IFSS) of the sizing. As a result, the CF/PEEK composites achieved the highest ever reported IFSS, with values of 101.4 MPa and 103.4 MPa in the acidified-CNT and PEEK-grafted-CNT samples, respectively. It is noted that the PEEK-grafted-CNT sample also exhibited greater solvent resistance due to closer interfacial distance, and an IFSS retention rate of 80%–90% in various polar and non-polar solvents. The successful application of nano-reinforcement in a CF interfacial sizing and the development of the PEEK grafting on CNT possesses an expanded application potential for CF/PEEK composites. [Display omitted] [ABSTRACT FROM AUTHOR]

Red deer (Cervus elaphus/hanglu/canadensis) are a group of closely-related species that survived through the Last Glacial period in Eurasia and expanded into North America. The evolutionary modes of red deer in Europe through glacial and interglacial cycles have been established relatively well based on both modern and ancient genomes, while the evolutionary and migratory history of red deer in Asia are not so clear. Northern China, as the southern border of their current distribution, is a significant area for exploring the evolution of wapitoids (Cervus canadensis). Here, we constructed six mitochondrial genomes (lengths of 13,282–16,306 bp) from Late Pleistocene fossil cervid materials in Northeastern China, and four modern complete mitochondrial DNA sequences (16,798–16943 bp) from Northern China. Phylogenetic analyses suggest four clades in wapitoids, with our new individuals clustered into three out of the four clades. BEAST analysis indicates that the divergence between elaphoids (including Cervus elaphus and Cervus hanglu) and the complex of 'wapitoids + sika deer (Cervus nippon)' occurred at approximately 1.37 million years ago (Ma, 95%Cl: 1.64–1.15 Ma). Bayesian skyline plots (BSPs) show that the effective maternal population size of wapitoids had a slight and stable expansion between Marine isotope stages (MIS) 7–3, and then shrank from the beginning of the Last Glacial Maximum (LGM). Combined with the divergence dates, population dynamics, and fossil findings in Northern China, we infer that after wapitoids migrated eastward from Central Asia to Northeastern Asia, they had multiple migrations southward into Northern China. The current distribution of wapitoids in Northern China was likely shaped by these migrations as well as habitat fragmentation. Meanwhile, the radiocarbon dates of ancient individuals indicate that the Northeast China Plain, located at the same latitude as European refugia, may have provided a refugium for megafaunal species such as red deer to survive the LGM. • First combined sampling of both ancient and extant mitogenomes of wapitoids in China. • Demonstrating habitat fragmentation or multiple migratory events of wapitoids in Northern China. • Indicating a possible refuge for megafauna species in Northeastern China in LGM. [ABSTRACT FROM AUTHOR]

The conductive chiral MWCNTs@NCC nanopapers obtained by the assembly of nanocrystalline cellulose liquid crystals (NCC LCs) host matrix along with one-dimensional (1-D) multi-walled carbon nanotubes (MWCNTs) have been studied in this work. Circular dichroism (CD) studies show strong signals stemming from the chiral nematic structure. Notably, the introduction of the MWCNTs has a pronounced effect on the chiral structure of the as-prepared nanopaper. Our experimental results indicate the multiple weak molecular interactions existing between MWCNTs and NCC are responsible for the effective dispersion and stabilization of MWCNTs. Moreover it also confirms the resulting nanopaper has an increased conductivity of 4.2 S/m at 1.96 wt% MWCNTs. So the co-assembly of the nanocomposite herein opens a gateway for preparing functional materials combining the photonic properties of the NCC LCs matrix with other building blocks that can supply other advantageous functions. [ABSTRACT FROM AUTHOR]

This study was conducted to clone and functionally characterize a full-length cDNA encoding arachidonate 5-lipoxygenase (Alox5) from large yellow croaker ( Larmichthys crocea ) and investigate its gene expression in response to graded dietary ratio of linolenic acid (ALA) to linoleic acid (LNA) (0.03, 0.06, 0.45, 0.90 and 1.51). An isolated 2372 bp cDNA clone of Alox5 contained an open reading frame spanning 2025 bp encoding a protein with the ability to modify arachidonate acid (AA) to 5-hydroxyeicosatetraenoic (5-HETE). In the liver, the Alox5 mRNA expression levels significantly increased to the maximum when the dietary ALA/LNA increased from 0.03 to 0.06, and then significantly decreased with dietary ALA/LNA increased to 1.51 ( P < 0.05). In the kidney, the expression levels of Alox5 of fish fed diets with low dietary ALA/LNA (0.03–0.06) were significantly higher than those of fish fed diets with high dietary ALA/LNA (0.45–1.51) ( P < 0.05). The dual-luciferase reporter assays showed that the nuclear factor kappa B (NF-κB) could act on cognate cis -acting elements in the promoter of Alox5 and increased the transcription of Alox5. Results of the present study suggested that the expression of Alox5 is higher in croakers fed high concentrations of LNA compared to those fed high concentrations of ALA, which might be regulated by NF-κB and contribute to the inflammation process by catalyzing the dioxygenation of AA. [ABSTRACT FROM AUTHOR]

Microporous polyimides (MPIs) have been acted a significant role in porous organic polymers (POPs) for gas capture and separation. However, the MPIs are mostly constructed from monomers with rigid 3D or twisted structures or hyperbranched precursors, and their porous structure is mainly tuned by changing the length of the constructed units. Herein, the cross-linkable linear PIs with flexible skeletons are selected as precursors to construct the cross-linked microporous polyimides (C-MPIs). The method has significant comparative advantages including abundant monomers, the convenience of synthesis, cost-effectiveness, structural diversity and designability. Moreover, the micropore size of the C-MPIs (6FA-PE-CL, 6FA-PEPH-CL) can be tuned from 0.64 nm to 0.57 nm through the side-chain engineering of the cross-linkable linear PI precursors. The BET surface area of the C-MPIs are ranging from 635 to 698 m2g-1 and is among the best results for the reported linear MPIs. The smaller pore size (0.57 nm), higher micropore surface area (378 m2g-1) and micropore volume (0.17 cm3g-1) endow 6FA-PE-CL with better CO 2 selective uptake capacity (8.9 wt% and 58) than those of 6FA-PEPH-CL (7.3 wt% and 38). This work provides a side-chain engineering method to tune the pore structure of MPIs, which has tremendous potential for constructing high-performance polymer networks with abundant ultramicroporous structure (<0.7 nm) based on flexible linear polymers. Microporous polymer networks with tunable micropore sizes have been constructed through the side-chain engineering of cross-linkable linear polyimide precursors. [Display omitted] • The microporous polymer networks with abundant ultramicropores were constructed from flexible linear polyimides. • The pore size can be finely tuned through the side-chain engineering method. • The microporous polyimide with a smaller pore size exhibits better CO 2 selective uptake capacity. [ABSTRACT FROM AUTHOR]

• This study responds to a call for rediscovering the role of socioeconomic status (SES) in studies of misinformation exposure and susceptibility. • Poisson regression models were fitted with the data coming from an online survey with 955 Chinese respondents. • Alternative sources use in mainland China is found to be positively related to misinformation exposure and susceptibility, respectively. • Socioeconomic status (SES), indicated by income levels, is found to quadratically moderate the relationship between alternative sources use and misinformation exposure/susceptibility. In contrast, educational attainment, another usual indicator of SES, does not show support for a quadratic moderation effect hypothesis. In an era of post-truth, the rise of alternative information sources is often blamed for the spread of misinformation. This study responds to a call for rediscovering the role of socioeconomic status (SES) by investigating the quadratic moderation effects of SES on associations between the use of alternative sources and misinformation exposure and susceptibility. Poisson regression models were fitted with the data coming from an online survey with 955 Chinese respondents. Findings show that the moderation effects are quadratic when income, rather than educational attainment, serves as the measurement of SES. The implications of the findings with respect to overeducation, income's cognitive effects, and the non-equivalence of SES's common measures in studies of media effects are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Streak Tube Imaging Lidar (STIL) is provided with the characteristics of high resolution, high detection sensitivity, and wide field of view (FOV). It is a new type laser radar, and has actual application. For the low-contrast condition, image segment becomes difficult to STIL, which will influence on the detection/recognizing rate. In order to resolve the problem, a new polarized STIL imaging system is presented. Its structure is designed, which is included a polarizer and a Wollaston prism to the transmitting and receiving system, respectively. The polarized STIL can simultaneously collect the two polarization images. Through image processing and computing, the intensity and DOP images with high resolution are obtained, which can provide the rich information of targets. The far distance imaging experiments that the part target is hidden in the clutter are carried out. The results state that the polarization images have high-contrast, and it is easy to segment target from the background. [Copyright &y& Elsevier]

Abstract: CO2 adsorption enhanced gasification process is a prospective technology to be used in hydrogen and power production with nearly zero CO2 emission. In this paper, a gasification kinetics steady state model is developed based on the chemical kinetics mechanism with the condition of fluidization. It is used to predict the parameters of gas phase and solid phase for a continuous flow reactor with steady state. The variation of distribution of components with gasification temperature and pressure are determined. Conceptual configurations of H2 and power co-production system are designed with the integration of CO2 adsorption enhanced gasification process, H2 separation unit, power generation unit and other auxiliary units. Mass and heat transfer between different parts are studied systematically by flow-sheet simulation and sensitivity analysis of parameters. According to the generalized exergy efficiency of the system, the influence of gasification temperature and pressure on the system performance is investigated and the optimum gasification temperature and pressure for system operation can be determined. [Copyright &y& Elsevier]

Abstract: To improve coke oven gas (COG) energy conversion, alternative configurations for amplifying hydrogen from COG are proposed in this paper. In these new configurations, a CO2 adsorption enhanced hydrogen amplification reactor is combined with a pressure swing adsorption separation unit (PSA) to produce pure hydrogen. Hydrogen production was integrated with desorption gas utilization, in situ CO2 capture and waste heat recovery to improve COG energy conversion efficiency and decrease CO2 emissions. To analyze the advantages of the flowsheet modifications, technical and economic performance indicators were used to evaluate and compare the performances of the various system configurations. Simulation results show that the alternative configurations proposed in this paper have higher energy conversion efficiencies, higher hydrogen yields and shorter dynamic payback periods. The variation of technical performance with reaction temperature, pressure, sorbent to carbon ratio and steam to carbon ratio were also analyzed using a sensitivity study. Optimal operating conditions for the CO2 adsorption enhanced hydrogen amplification reactor were obtained based on the simulation results. [Copyright &y& Elsevier]

In recent years, building microporous polyimides (MPIs) via choosing simple commercial aromatic monomers or concise experimental methods is still an issue worthy to explore. Herein, two cross-linkable aromatic alkynyl monomers (TAPM-PEPA and TAPA-PEPA) were prepared from a commercial alkynyl anhydride PEPA and two aromatic multi-amine TAPM (3D-tetrahedron) and TAPA (near 2D-planar) monomers with different topological structures. The crosslinked polyimides were prepared and endowed microporous features via one-pot thermal crosslinking polymerization in the diphenyl sulfone. The TAPM-PEPA-CL has higher BET surface area and total pore volume (736 m2 g-1 and 0.497 cm3 g-1) than those of the TAPA-PEPA-CL (351 m2 g-1 and 0.358 cm3 g-1). As the topological structure becomes more stereoscopic, CO2 adsorption capacity has been significantly improved from 9.6 wt% to 13.5 wt%. Furthermore, the TAPM-PEPA-CL and TAPA-PEPA-CL have excellent selectivity for CO 2 /CH 4 (12.0–23.6) and CO 2 /N 2 selectivity (54.4–57.6) at 273 K and 1 bar. These results reveal that the introduction of crosslinked structures and control of topological structures have potential application significance for preparing microporous polyimides based on cross-linkable aromatic alkynyl monomers, which is beneficial for the development of the field of gas adsorption and selectivity. [Display omitted] • The crosslinked microporous polyimides were successfully prepared via commercial one-pot thermal crosslinking polymerization. • The porous performance can be tuned by changing topological structures of the precursors. • The crosslinked polyimides show favorable CO 2 adsorption (9.6–13.5 wt%) as well as excellent selectivity for CO 2 /CH 4 (12.0–23.6) and CO 2 /N 2 selectivities (54.4–57.6) at 273 K and 1 bar. [ABSTRACT FROM AUTHOR]

In recent years, linear polyimides of intrinsic microporosity have been widely used in the field of gas adsorption and separation because of their high BET surface area and microporous structures. Most of the microporous structures come from the twisted main-chain structures in the linear polyimides of intrinsic microporosity. Therefore, most linear polyimides (PI) without twisted structure have no porosity. Herein, to construct the linear polyimide with microporous structure, a sequence of microporous polyimides (PIs-CL) were constructed from the flexible linear polyimide precursors through the thermal crosslinking reaction. The polyimide precursors without twisted structure were synthesized from a well-designed diamine TFVBPA with cross-linkable ethynyl groups and several commercial dianhydrides (ODPA, BPDA, PMDA and 6FDA) by polycondensation to research the influence of the main-chain structure on the porous characters. The introduction of crosslinked structures gives the linear crosslinked polyimides (PIs-CL) with porous structures. The PIs-CL show obviously improved porosity (0.52–1.71 nm) and higher BET surface area (337–618 m2 g−1) than those of the uncrosslinked polyimides (PIs). Moreover, PIs-CL have favorable CO 2 adsorption (5.7–9.3 wt%) as well as good CO 2 /N 2 selectivity (34.4–58.5) at 273 K, which are better than other polyimides materials. The introduction of crosslinked structures is an effective way to improve microporous porosity and gas sorption performance. Image 1 • The PIs-CL were successfully prepared via polycondensation and thermal crosslinking reaction. • The porous performance can be tuned by inducting crosslinked structure and changing main-chain structures. • The PIs-CL show excellent pore size (0.52–1.71 nm) and favorable CO 2 adsorption (5.7–9.3 wt%) at 273 K. [ABSTRACT FROM AUTHOR]

SMC3 encodes a subunit of the cohesin complex that has canonical roles in regulating sister chromatids segregation during mitosis and meiosis. Recurrent heterozygous mutations in SMC3 have been reported in acute myeloid leukemia (AML) and other myeloid malignancies. In this study, we investigated whether the missense mutations in SMC3 might have dominant-negative effects or phenocopy loss-of-function effects by comparing the consequences of Smc3 -deficient and -haploinsufficient mouse models. We found that homozygous deletion of Smc3 during embryogenesis or in adult mice led to hematopoietic failure, suggesting that SMC3 missense mutations are unlikely to be associated with simple dominant-negative phenotypes. In contrast, haploinsufficiency was tolerated during embryonic and adult hematopoiesis. Under steady-state conditions, Smc3 haploinsufficiency did not alter colony forming in methylcellulose, only modestly decreased mature myeloid cell populations, and led to limited expression changes and chromatin alteration in Lin–cKit+ bone marrow cells. However, following transplantation, engraftment, and subsequent deletion, we observed a hematopoietic competitive disadvantage across myeloid and lymphoid lineages and within the stem/progenitor compartments. This disadvantage was not affected by hematopoietic stresses, but was partially abrogated by concurrent Dnmt3a haploinsufficiency, suggesting that antecedent mutations may be required to optimize the leukemogenic potential of Smc3 mutations. [ABSTRACT FROM AUTHOR]

The precise control of porous structure has always been a key factor for porous materials. We tuned the porous structures by enhancing alkynyl-groups contents and introducing metal into porphyrin ring. We used simple polymerization and alkynyl crosslinking reactions to construct crosslinked porous porphyrin-based polyimides (CR-PPBPIs) from 2,5-bis(3,4-dicarboxyphenoxy)-4'-phenylethynyl-biphenyl dianhydride (PEPHQDA) and 5,10,15,20-tetra[4-[(3-aminophenyl)ethynyl]phenyl] porphyrin (TAPEPP). CR-PPBPIs revealed BET surface areas (212, 578 and 593 m2 g−1), dominated pore width (1 and 1.9 nm) and abundant CO 2 -philic substances. Thus, considerable CO 2 uptakes (1.92, 2.43 and 2.52 mmol g−1), CO 2 -adsorption isosteric enthalpies (31.9, 26.0 and 27.9 kJ mol−1) and superior CO 2 /N 2 selectivities (45.77, 38.72 and 46.26) were achieved. This work sheds some light on the precise regulation of porosity parameters in the crosslinked metalloporphyrin-based polyimides for carbon dioxide adsorption and separation. [Display omitted] • We tuned the porous structures by changing alkynyl-groups contents and metals. • CR-PPBPIs revealed dominated micropores and abundant CO 2 -philic substances. • CR-PPBPIs exhibited considerable CO 2 uptakes and CO 2 /N 2 selectivities. [ABSTRACT FROM AUTHOR]

• The oxygen contents have different effects on PCDD and PCDF formation. • Much more PCDD/Fs was formed from 1,2,3-TrCBz with iron oxides than copper oxides. • The major EPFRs on catalysts were formed with g values in the range of 2.0040 to 2.0049. The formation of dibenzofuran (DF), polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD/Fs) and environmentally persistent free radicals (EPFRs) from 1,2,3-trichlorobenzene (1,2,3-TrCBz) over metal oxide / silica surface were investigated using a tubular furnace. PCDD/Fs increased exponentially from 250 to 550 °C over copper oxide / silica surface and PCDD/Fs had the maximum growth from 400 to 450 °C. The ratio of PCDD / PCDF was much less than 1, especially when the temperature raised from 450 to 550 °C. Pentachlorianated dibenzo- p -furan (PeCDF) dominated among the homologues, which contributed 45–61% to the total PCDD/Fs. Two peaks of the yield of DF occurred at 400 °C and 500 °C respectively. Furthermore, the oxygen contents have different effects for PCDD and PCDF formation, and low oxygen could promote PCDD production, especially for tetrachlorinated dibenzo- p -dioxin (TCDD). More PCDF were formed on the oxygen rich condition, indicating that the oxygen promoted the chlorination of DF. Iron oxides are better than copper oxides to catalyze the formation of PCDD/Fs from 1,2,3-TrCBzs at 350 °C, especially for PCDF. The major EPFRs on the catalysts were formed with g values in the range of 2.0040 to 2.0049, which were phenoxy radicals and semiquinone occurred with higher g value of 2.0075 when the temperature increased to 550 °C, and more EPFRs were produced with the temperature increasing. The addition of iron oxides reduced the spins concentrations of oxygen-centered radicals but increase the spins concentrations of signals with lower g values. The different possible formation pathways of PCDD and PCDF from 1,2,3-TrCBz over metal oxide surface were also proposed. [ABSTRACT FROM AUTHOR]

CXCR3, a G-protein coupled chemokine receptor, has been found to be overexpressed in many tumors and act as an independent prognostic marker. However, it is still unclear whether CXCR3 is involved in gastric cancer progression. In this study, we found that CXCR3 was markedly expressed in gastric cancer cells and tissues. High CXCR3 expression correlated with advanced tumor stage, vascular invasion, lymph node metastasis and poor survival of gastric cancer patients. Activation of CXCR3 by one of its ligands CXCL10 promoted the invasion and migration of gastric cancer BGC-823 and MGC-803 cells, and increased the secretion and activities of MMP-2 and MMP-9. However, the effects of CXCL10 on gastric cancer cells were attenuated by CXCR3 siRNA transfection. Furthermore, overexpression of CXCR3 enhanced CXCL10-mediated cell invasion and migration of gastric cancer MKN28 cells. In addition, CXCR3 time-dependently induced activation of AKT. PI3K/AKT pathway was required for CXCR3-mediated gastric cancer cell invasion, migration and MMP-2/9 production. Together, our findings suggest that CXCL10/CXCR3 axis promotes gastric cancer cell invasion and migration by upregulating MMP-2 and MMP-9 production via PI3K/AKT pathway. Thus, CXCR3 could be a potential target for the gastric cancer treatment. [ABSTRACT FROM AUTHOR]

• The underlying mechanism of relaxation and redistribution of residual stress under cyclic loading were analyzed. • The correlation between redistributed residual stress and fatigue fracture behavior was discussed. • The role of residual stress on the fatigue performance of weld joints was revealed. • A fatigue life prediction model of weld joints was proposed by considering the residual stress and its redistribution. Weld residual stresses have a great effect on the fatigue strength of welding structures. As an internal stress, the residual stress is unfounded to be treated as the conventional mechanical load during the fatigue safety assessment due to its relaxation and redistribution under cyclic loading. Thus, establishing an accurate model considering the effects of residual stress is critical for fatigue strength design. Therefore, this paper develops a sequential coupling residual stress analysis and a cyclic viscoplastic constitutive model to predict the residual stress evolution and its role on the fatigue life, which has been validated by an experimental measurement of residual stress and a SEM-based observation fatigue fracture morphology. The results show that the role of residual stress on fatigue life is mainly reflected by the increase of mean stress, and its increased magnitudes depends on the stress redistribution. The redistribution of residual stresses is closely correlated to the fatigue fracture behavior of weld joints. And a fatigue life prediction model of weld joints is proposed based on the experimental data of base metal by further considering the residual stress and its redistribution. Finally, the experimental results verify the proposed model on predicting both the fatigue failure location and lives of weld joints, and the predicted lives are within the 1.5 error band. [ABSTRACT FROM AUTHOR]

Bright crescent areas were obviously apparent at the bottom of melt pools of Inconel 718 samples prepared by selective laser melting (SLM). Their microstructure, composition, spatial morphology, and mechanical behaviors were systematically investigated. These areas consisted of finer columnar dendrites with underdeveloped secondary arms, which resulted in a bright color under optical field and dark color under SEM. Both growth and crystal orientations were consistent with those of the grains in the melt pool of the former layer. Enrichment of elements Nb and Ti occurred among the dendrites in these areas, leading to the formation of Laves phases. The crescent areas underwent great deformation together with the melt pools during tensile testing, which showed that they were of great plasticity and no gaps or cracks were found around these areas. In addition, the bright crescent areas possessed higher hardness than that of the surrounding regions. Furthermore, the simulated temperature field results showed that the incomplete re-melting of the formed dendrites and a large number of nucleated dendrites among them are the main reasons for the formation of the bright crescent areas. Unlabelled Image • A kind of bright crescent-shaped areas was obviously found at the bottom of melt pools. • The bright areas were composed of finer columnar dendrites with orientation consistent with the former melt pools. • The bright crescent areas had higher hardness. • The incomplete remelting of the former layer led to the formation of the bright crescent areas. [ABSTRACT FROM AUTHOR]

Microporous polyimides have been extensively investigated for CO 2 capture and separation applications. Here, the crosslinked structure and the polar CO 2 -philic trifluoromethyl group are introduced into the hyperbranched polyimides to construct the microporous polyimide networks for efficient CO 2 capture. The HBPI-CL networks exhibit significant increased micropores (pore size less than 1 nm) surface area and volume ranging from 79 to 89 m2g-1 and 0.03–0.05 cm3 g−1. It is intriguingly found that the CF 3 TAPA-HBPI-CL have more abundant ultramicropores and exhibit higher CO 2 uptake capacity and CO 2 /N 2 selectivity (8.56 wt% and 33.3) than those of TAPA-HBPI-CL (7.47 wt% and 20.4) without the polar CO 2 -philic trifluoromethyl group at 273 K/1 bar. This work reveals that the introduction of polar CO 2 -philic trifluoromethyl group into crosslinked polyimides is an effective method to improve the CO 2 adsorption capacity and selectivity of microporous polyimide, which can be also applied to other microporous polymers. Microporous polyimide networks with efficient CO 2 capture performance have been constructed by introducing crosslinked structure and polar trifluoromethyl group into hyperbranched polyimides. Image 1 • The microporous polyimides (HBPI-CLs) with different substituent groups were prepared. • The polar trifluoromethyl group can facilitate the formation of ultramicropores and enhance the affinity for CO 2 molecule. • The CF 3 TAPA-HBPI-CL exhibit higher CO 2 uptake capacity and CO 2 /N 2 selectivity (8.56 wt% and 33.3) than TAPA-HBPI-CL (7.47 wt% and 20.4) at 273 K and 1 bar. [ABSTRACT FROM AUTHOR]