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Group 3 innate lymphoid cells (ILC3s) control the formation of intestinal lymphoid tissues and play key roles in intestinal defense. They express neuropeptide vasoactive intestinal peptide (VIP) receptor 2 (VPAC2), through which VIP modulates their function, but whether VIP exerts other effects on ILC3 remains unclear. We show that VIP promotes ILC3 recruitment to the intestine through VPAC1 independent of the microbiota or adaptive immunity. VIP is also required for postnatal formation of lymphoid tissues as well as the maintenance of local populations of retinoic acid (RA)–producing dendritic cells, with RA up-regulating gut-homing receptor CCR9 expression by ILC3s. Correspondingly, mice deficient in VIP or VPAC1 suffer a paucity of intestinal ILC3s along with impaired production of the cytokine IL-22, rendering them highly susceptible to the enteric pathogen Citrobacter rodentium. This heightened susceptibility to C. rodentium infection was ameliorated by RA supplementation, adoptive transfer of ILC3s, or by recombinant IL-22. Thus, VIP regulates the recruitment of intestinal ILC3s and formation of postnatal intestinal lymphoid tissues, offering protection against enteric pathogens.

ObjectiveHyperglycemia and type 2 diabetes (T2D) are caused by failure of pancreatic beta cells. The role of the gut microbiota in T2D has been studied but causal links remain enigmatic.DesignObese individuals with or without T2D were included from two independent Dutch cohorts. Human data was translated in vitro and in vivo by using pancreatic islets from C57BL6/J mice and by injecting flagellin into obese mice.ResultsFlagellin is part of the bacterial locomotor appendage flagellum, present on gut bacteria including Enterobacteriaceae, which we show to be more abundant in the gut of individuals with T2D. Subsequently, flagellin induces a pro-inflammatory response in pancreatic islets mediated by the Toll-like receptor (TLR)-5 expressed on resident islet macrophages. This inflammatory response associated with beta-cell dysfunction, characterized by reduced insulin gene expression, impaired proinsulin processing and stress-induced insulin hypersecretion in vitro and in vivo in mice.ConclusionWe postulate that increased systemically disseminated flagellin in T2D is a contributing factor to beta cell failure in time and represents a novel therapeutic target.Graphical abstract

With the aim of relieving the serious environmental and climate issues arising from excessive emission of anthropogenic CO

Reducing food intake is a common host response to infection, yet it remains unclear whether fasting is detrimental or beneficial to an infected host. Despite the gastrointestinal tract being the primary site of nutrient uptake and a common route for infection, studies have yet to examine how fasting alters the host’s response to an enteric infection. To test this, mice were fasted before and during oral infection with the invasive bacterium Salmonella enterica serovar Typhimurium. Fasting dramatically interrupted infection and subsequent gastroenteritis by suppressing Salmonella’s SPI-1 virulence program, preventing invasion of the gut epithelium. Virulence suppression depended on the gut microbiota, as Salmonella’s invasion of the epithelium proceeded in fasting gnotobiotic mice. Despite Salmonella’s restored virulence within the intestines of gnotobiotic mice, fasting downregulated pro-inflammatory signaling, greatly reducing intestinal pathology. Our study highlights how food intake controls the complex relationship between host, pathogen and gut microbiota during an enteric infection., Author summary Most animals, including humans, lose their appetites when sick. Whether this sickness behavior has evolved as a protective mechanism is unclear. In addition, fasting therapies have become popular in recent years and show promise for treating chronic inflammatory diseases, but it is uncertain whether fasting-induced immunosuppression could leave an already fasted host more vulnerable to infection than a fed host. To test this, we fasted mice and orally infected them with the invasive bacterium Salmonella Typhimurium. This pathogen causes gastroenteritis (food poisoning) in humans and in antibiotic-pretreated mice. Notably, the fasted mice were protected from infection. While Salmonella rapidly expanded in the intestines of fed mice, their expansion was reduced in fasted mice. Moreover, Salmonella in the fasted mice did not cause any intestinal tissue damage as the bacteria were unable to invade the intestinal wall. This protection was found to be partially due to the gut microbiome, since fasting was unable to prevent Salmonella infection in mice lacking a microbiome, although the mice suffered less gastroenteritis. We therefore conclude that fasting can protect hosts from intestinal bacterial infections, in part through the actions of the gut microbiome.

A coupled electrochemical system (CES) for the electroreduction of CO2 to formate (ERCF) and simultaneous degradation of organic pollutants is a promising approach for CO2 conversion. Cathode material is a critical component of CES. However, the poor performance and complexity of synthesis limit its real application. Here, we report a Bi-based binder-free gas diffusion electrode (EBGDE) as a high-performance cathode for CES. The EBGDE was fabricated via direct electrodeposition of Bi nanosheets on a gas diffusion layer. By optimizing the deposition time of Bi nanosheets, a good Faraday efficiency (91.46 ± 6.58%) and formate production rate (1849.96 ± 127.69 μmol m−2 s−1) were obtained. Simultaneously, the methyl orange decolorization efficiency and chemical oxygen demand removal efficiency reached 100% and 55.25 ± 6.87%, respectively. This performance towards ERCF is better than recently reported ERCF electrodes. It probably results from the excellent performance of associated Bi-nanosheets catalysts, a high electroactive surface area, as well as fast electron transfer in the EBGDE. This work offers design rules to fabricate high-performance cathode materials for CES in industrial applications.

In-situ heavy ion (1 MeV Kr2+) irradiation was carried out to investigate the evolution of irradiation induced lattice defects at room temperature and the stability of β-Zr under irradiation at temperatures ranging from 150 to 350 °C. It was found that the irradiation induced defects started to appear at a dose between 0.5 dpa and 0.75 dpa, which is relatively high compared to the case for α-Zr. The number density of dislocation loops increased exponentially with fluence, with an exponential index ∼3.52. The statistical results show that the electron beam with which in-situ observation was carried out had an influence on the size of the dislocation loops. The g·b analysis shows that dislocation loops with Burgers vector ½ 1 ¯ 11> and are both present in the sample after irradiation to 1.5 dpa. ω phase particles precipitate out during irradiation at 250 and 350 °C, as a result of the combination of the thermal treatment and irradiation enhanced concentration of point defects.

This work aims to degrade a typical antibiotic Norfloxacin (NOR) in saline water with a novel green carbon black based Ti/SnO2-Sb electrochemical catalysis system (TSSC), with Ti/SnO2-Sb as anode (TSSA) and a novel carbon black air diffusion electrode as cathode (CBAC). An electrochemical system with TSSA and a platinum carbon (Pt/C) cathode was used as control (TSSP). The removal ratio, degradation condition and the biodegradability were evaluated, the degradation pathway and mechanism were investigated. The result showed an efficient removal performance in both TSSC and TSSP systems. The removal ratio dropped with the lower current densities and higher initial pollutant loading. A considerable better removal performance was found in TSSC system, compared to that in TSSP system, when the low current density and saline concentration were applied. Meanwhile, 25.7% and 23.0% of COD removal ratios were obtained in TSSP and TSSC systems, respectively, in a short reaction time (25 min) and a very slight current density (0.18 mA cm−2). However, the TSSC showed a much more significant improvement of NOR biodegradability than that in TSSP system, indicating a considerable potential of TSSC system for both individual application and synergistic working with traditional bio-degradation system for refractory antibiotics treatment.

A direct comparison between the microstructural evolution during the annealing of a TEM thin foil (thickness ~100 nm) and the bulk material of Zr-2.5Nb-0.5Cu alloy is presented. The results indicate that at an intermediate temperature, (550 °C), diffusion-controlled phenomena such as boundary migration and precipitate coarsening are retarded in the thin foil due to a thickness effect. At high temperature, (815 °C), the chain of transformations a) Widmanstatten → α + β, b) precipitate dissolution in the matrix and c) precipitation at the β phase is observed in the bulk material. In the thin foil, however, sufficient activation energy for the first transformation is not provided; consequently, growth of the initial precipitates with a smaller energy barrier progresses. Possible transformation retardation mechanisms in thin foils are discussed.

Based on the geometry and surface in Daya Bay, we artificially divided the reclamation projects into three periods to analyze the influences and changes on hydrodynamic conditions as a result of the reclamation projects. Three periods of tidal current fields, tidal prisms, and water exchange capacity are simulated by the Finite-Volume, primitive equation Community Ocean Model and the characteristics and trends of hydrodynamics in Daya Bay are discussed. The combination of observation and simulation in this paper gives a good description on the tidal dynamic system in Daya Bay. As indicated by model results, the tidal current velocity in the Bay totally decreases after numerous activities associated with reclamation construction. The decreasing current velocity region is mainly distributed near the Xiachong and Gangkou chain islands. The current velocity in 2015 decreases by approximately 5 cm s−1 compared with velocities before 2000. Future reclamation activities will exacerbate these decreasing current velocity trends in some regions. Compared with 2015, the tidal prism has significantly decreased by 1.3622 × 107 m3 due to planned reclamation. The half-water exchange times for Daya Bay in 2015 and after planned reclamation are 178.9 and 177.4 days, respectively. The water exchange capacity in Fanhe Harbor is weaker than other water fields throughout Daya Bay.

A series of solid electrolyte cells with La0.8Sr0.2MnO3 (LSM)-Ce0.8Sm0.2O1.9 (SDC) composite cathodes was fabricated for the electrochemical decomposition of nitric oxide (NO). The LSM and SDC powders were synthesized by a combined EDTA-citrate method. Thermogravimetry with differential scanning calorimetry, X-ray diffraction analysis, scanning and transmission electron microscope with electron diffraction were performed to characterize the synthesized powders. The NO conversions and power consumptions of the solid electrolyte cells with the cathodes sintered at 900–1200 °C were evaluated. The electrochemical properties, microstructures, and crystalline phases of the cathodes were further studied by electrochemical impedance spectrum, scanning electron microscope and X-ray diffraction, respectively. The NO conversions and electrochemical performances of the cells at different operating temperature were also investigated. It was concluded that the LSM and SDC powders calcined at 900 °C both showed good crystal structures with high purity. The cell with the cathode sintered at 1100 °C had the highest NO conversion of 65.4% and the lowest power consumption of 0.2024 W under 80 mA applied current. The total polarization resistances of the cells with the cathodes sintered at 900–1200 °C were 63.32, 41.75, 38.11 and 97.57 Ω cm2 in 800 ppm NO, respectively. The cathode sintered at 900 °C had an incompact structure and connected with the electrolyte loosely, thereby impeding the NO adsorption on the cathode surface and the transfer of O2− from three phase boundary (TPB) to electrolyte. The excess sintering temperature of 1200 °C resulted in a dense structure of cathode and La2Zr2O7 formation at the interface between the cathode and electrolyte, thereby leading to a poor NO decomposition performance. This study also found that the NO conversion increased with the rise of operating temperature and 600 °C was not suitable for operation because of the electrode degradation caused by the overvoltage.

NOx is a significant atmospheric pollutant triggering haze weather. The existing DeNOx technology has drawbacks of needing additional reducing agent and high working temperature. In order to overcome those defects, a novel La0.6Sr0.4Fe0.8Mn0.2O3 (LSFM)-modified gas diffusion electrode (GDE) was prepared to establish an in-situ electrochemical DeNOx process. The DeNOx efficiency was enhanced by increasing Nafion and polytetrafluoroethylene (PTFE) content in the GDE within an appropriate range. Nafion created the proton transport pathway of electrolyte-Nafion-three phase interfaces (TPIs) and PTFE improved the hydrophobic gas channels. The highest DeNOx efficiency of 71.1% was obtained with inlet NOx of 1000 ppm under ambient temperature (25 °C) when the mass ratio of LSFM:Nafion:PTFE was 1:0.117:0.23. In the electrochemical DeNOx process, i) NOx was absorbed by the gas diffusion layer and then transferred to the catalyst layer through the hydrophobic channels; ii) NOx was electrochemically decomposed to N2 and O2− under the catalysis of LSFM; iii) O2− was transformed to OH− on the TPIs by combining with H+ and oxidized to O2 in the anode. Simultaneously N2 was released. Its advantages of no reducing agent, mild operating condition and high energy-efficiency indicate great potential for practical application.

In this paper, 40 MeV Zr ion irradiation of Zr-2.5Nb pressure tube alloy was carried out, delivering a damage layer 6.5 μm deep. Uniaxial micropillar compression experiments along the tube axial (AD) and transverse directions (TD) were conducted. Irradiation was found to alter the deformation mechanisms and to increase the yield strength more in the AD oriented pillars than TD pillars for irradiation up to 0.6 dpa. This anisotropy in response is discussed in terms of the limitations of the micropillar compression method and the different deformation mechanisms which are activated in each orientation. The anisotropic hardening effect of -type dislocation loops on prismatic , basal , and pyramidal slip systems is also discussed. The micropillar compression results were also compared with nanoindentation results conducted on the same material.

Electrochemical removal of nitrogen oxides (NO

The application of fertilizer can improve the Cd enrichment efficiency of plants, but the changes of nitrogen (N), phosphorus (P), potassium (K) in the growth medium have different impacts on Cd enrichment efficiency of plants. In this study, hydroponic experiment by adding different KNO3 and (NH4)3PO4 was carried out to study whether and how the addition of available N, P and K can improve Cd accumulation. The four treatments were CK, 0.4 mg kg-1 Cd (Cd), 0.4 mg kg-1 Cd and KNO3 (COK), 0.4 mg kg-1 Cd and (NH4)3PO4 (CNP). The results showed that the chlorophyll contents, PSII maximum photochemical quantum efficiency (Fv/Fm) and PSII potential activity (Fv/Fo) of COK and CNP were higher than that of CD. There was no significant difference between CK and CNP (P > 0.05). The N, P and K contents and Cd concentrations of roots and stems of COK and CNP were significantly higher than those of CD(P＜0.05).The BCF of COK and CNP were also significantly higher than that of CD, increasing by 39.8% and 37.6%, respectively. The root, stem and leaf dry weight of COK and the root and stem dry weight of CNP were higher than that of CD, and the biomass of the whole basin was significantly higher than that of CD (P＜0.05), but with no significant difference from that of CK (P＞0.05). In addition to stem K accumulation of CNP, N, P and K allocated to root and stem in COK and CNP were significantly higher than that in CD (P＜0.05). There was no significant difference in pH and water soluble Cd content among CD, COK and CNP (P＞0.05). it was concluded that plants can improve their Cd accumulation ability by changing biomass and nutrient allocation. The conclusion provides a theoretical basis for improving soil environmental factors by improving fertilization strategies of related plants so as to improve Cd enrichment ability.

BackgroundThe prompt diagnosis of pulmonary tuberculosis (PTB) remains a challenge in clinical practice. The present study aimed to optimize an algorithm for rapid diagnosis of PTB in a real-world setting.Methods28,171 adult inpatients suspected of having PTB in China were retrospectively analyzed. Bronchoalveolar lavage fluid (BALF) and/or sputum were used for acid-fast bacilli (AFB) smear, Xpert MTB/RIF (Xpert), and culture. A positive mycobacterial culture was used as the reference standard. Peripheral blood mononuclear cells (PBMC) were used for T-SPOT.TB. We analyzed specimen types’ effect on these assays’ performance, determined the number of smears for diagnosing PTB, and evaluated the ability of these assays performed alone, or in combination, to diagnose PTB and nontuberculous mycobacteria (NTM) infections.ResultsSputum and BALF showed moderate to substantial consistency when they were used for AFB smear or Xpert, with a higher positive detection rate by BALF. 3-4 smears had a higher sensitivity than 1-2 smears. Moreover, simultaneous combination of AFB and Xpert correctly identified 44/51 of AFB+/Xpert+ and 6/7 of AFB+/Xpert- cases as PTB and NTM, respectively. Lastly, when combined with AFB/Xpert sequentially, T-SPOT showed limited roles in patients that were either AFB+ or Xpert+. However, T-SPOTMDC (manufacturer-defined cut-off) showed a high negative predicative value (99.1%) and suboptimal sensitivity (74.4%), and TBAg/PHA (ratio of Mycobacterium tuberculosis-specific antigens to phytohaemagglutinin spot-forming cells, which is a modified method calculating T-SPOT.TB assay results) ≥0.3 demonstrated a high specificity (95.7%) and a relatively low sensitivity (16.3%) in AFB-/Xpert- patients.ConclusionsConcurrently performing AFB smear (at least 3 smears) and Xpert on sputum and/or BALF could aid in rapid diagnosis of PTB and NTM infections in a real-world high-burden setting. If available, BALF is preferred for both AFB smear and Xpert. Expanding this algorithm, PBMC T-SPOTMDC and TBAg/PHA ratios have a supplementary role for PTB diagnosis in AFB-/Xpert- patients (moderately ruling out PTB and ruling in PTB, respectively). Our findings may also inform policy makers’ decisions regarding prevention and control of TB in a high burden setting.

Combining spatially resolved X-ray Laue diffraction with atomic-scale simulations, we observe how ion-irradiated tungsten undergoes a series of non-linear structural transformations with increasing irradiation exposure. Nanoscale defect-induced deformations accumulating above 0.02 displacements per atom (dpa) lead to highly fluctuating strains at ~0.1 dpa, collapsing into a driven quasi-steady structural state above ~1 dpa. The driven asymptotic state is characterized by finely dispersed vacancy defects coexisting with an extended dislocation network, and exhibits positive volumetric swelling due to the creation of new crystallographic planes through self-interstitial coalescence, but negative lattice strain., Comment: 9 pages, 9 figures, in print with PRL

The type VI secretion system (T6SS) is a contractile nanomachine widely distributed among pathogenic and commensal Gram-negative bacteria. The T6SS is used for inter-bacterial competition to directly kill competing species; however, its importance during bacterial infection in vivo remains poorly understood. We report that the murine pathogen Citrobacter rodentium, used as a model for human pathogenic Escherichia coli, harbors two functional T6SSs. C. rodentium employs its T6SS-1 to colonize the murine gastrointestinal tract by targeting commensal Enterobacteriaceae. We identify VgrG1 as a C. rodentium T6SS antibacterial effector, which exhibits toxicity in E. coli. Conversely, commensal prey species E. coli Mt1B1 employs two T6SSs of its own to counter C. rodentium colonization. Collectively, these data demonstrate that the T6SS is a potent weapon during bacterial competition and is used by both invading pathogens and resident microbiota to fight for a niche in the hostile gut environment.

With the aim of relieving the serious environmental and climate issues arising from excessive emission of anthropogenic CO2, extensive solid absorbents have been developed for CO2 capture. Among them, porous boron nitride (BN) is considered an ideal candidate due to its high specific surface area, abundant structural defects, low density, and outstanding chemical inertness. Herein, BN absorbents were synthesized from pyrolysis of melamine-boric acid precursors, and the effect of pyrolysis temperature (900, 1000, 1050 and 1100 °C) on the properties and performances was investigated. Various characterizations were performed to evaluate the physicochemical properties and CO2 uptake capacities of BN absorbents. The result demonstrated that a carbon-doped BN structure was achieved instead of a pure BN material, and the carbonization degree was enhanced with the increase of pyrolysis temperatures. BN absorbent pyrolyzed at 1100 °C exhibited the highest CO2 adsorption capacity of 3.71 mmol/g (273 K). The reason should be that the doping of carbon in the framework of BN contributed to the formation of abundant micropores, which enhanced the physical adsorption by offering more adsorption sites. At the same time, more negative charges on BN were induced by structural defects, which favored the chemical adsorption of CO2 by invoking charge-induced chemisorption interaction. This study clarified the role of pore structure and electronic structure defects in CO2 adsorption capacity of carbon-doped BN, which would open up more spacious avenues for the development of promising BN-based absorbents, or even catalysts.

International audience; Ulcerative colitis (UC) is a chronic inflammatory condition linked to intestinal microbial dysbiosis, including the expansion of E. coli strains related to extra-intestinal pathogenic E. coli. These "pathobionts" exhibit pathogenic properties, but their potential to promote UC is unclear due to the lack of relevant animal models. Here, we established a mouse model using a representative UC pathobiont strain (p19A), and mice lacking single immunoglobulin and toll-interleukin 1 receptor domain (SIGIRR), a deficiency increasing susceptibility to gut infections. Strain p19A was found to adhere to the cecal mucosa of Sigirr-/-mice, causing modest inflammation. Moreover, it dramatically worsened dextran sodium sulfate-induced colitis. This potentiation was attenuated using a p19A strain lacking α-hemolysin genes, or when we targeted pathobiont adherence using a p19A strain lacking the adhesin FimH, or following treatment with FimH antagonists. Thus, UC pathobionts adhere to the intestinal mucosa, and worsen the course of colitis in susceptible hosts.

Coupling of nano-indentation and crystal plasticity finite element (CPFE) simulations is widely used to quantitatively probe the small-scale mechanical behaviour of materials. Earlier studies showed that CPFE can successfully reproduce the load-displacement curves and surface morphology for different crystal orientations. Here, we report the orientation dependence of residual lattice strain patterns and dislocation structures in tungsten. For orientations with one or more Burgers vectors close to parallel to the sample surface, dislocation movement and residual lattice strains are confined to long, narrow channels. CPFE is unable to reproduce this behaviour, and our analysis reveals the responsible underlying mechanisms.

One of the primary tools for diagnosing COVID-19 is the nucleic acid-based real-time reverse transcriptase-polymerase chain reaction (RT-PCR) test performed on respiratory specimens. The detection rate of SARS-CoV-2 in lower respiratory specimens (such as sputum) is higher than that for upper respiratory specimens (such as nasal and pharyngeal swabs). However, sputum specimens are usually quite viscous, requiring a homogenization process prior to nucleic acid (NA) extraction for RT-PCR. Sputum specimens from COVID-19 and non-COVID-19 patients were treated with four commonly used reagents-saline, N-acetyl-L-cysteine (NALC), proteinase K (PK), and dithiothreitol (DTT), prior to NA extraction. These reagents were then compared for their performance in diagnosing COVID-19 in real clinical practice. The detection rate of SARS-CoV-2 in PK- or DTT-treated sputum was comparable, and higher than that in sputum treated with NALC or saline. While there was a 4.8% (1/21) false negative rate for the PK- and DTT-treated sputum, neither treatment showed any false positive cases among patients with non-COVID diseases. Moreover, sputum pretreated with saline, NALC, PK or DTT showed higher detection rates of SARS-CoV-2 as compared to pharyngeal swabs. Taken together, we provide direct evidence recommending the use of PK or DTT to pretreat sputum samples to facilitate SARS-CoV-2 detection by clinical laboratories. Moreover, our methods should help to standardize the procedure of processing sputum specimens and improve the ability to detect SARS-CoV-2 in these samples.

Background Dental anxiety (DA) has an impact on the quality of dental treatment and may have long-lasting implications for children. A recent study introducing experiential learning (EL) into children’s oral health promotion resulted in better oral hygiene. The purpose of the study is to evaluate whether EL can reduce children’s DA. Methods In September 2018, we recruited 988 children aged 7–8 years from 24 classes to participate in a cluster-randomized trial. Classes were randomly assigned to EL (in which children received a lively presentation on oral health and participated in a role play in a simulated dental clinic in the classroom) or the Tell-Show-Do (TSD) group (in which children received a conventional TSD behavior management). The primary outcome was the prevalence of high DA after the procedure of pit and fissure sealant (PFS), assessed by a modified Children’s Fear Survey Schedule-Dental Subscale. Secondary outcomes were changes in blood pressures (BP) and pulse rates (PR) before and after the PFS procedure. The intervention effects were estimated by means of mixed effect models, which included covariates of gender and school (and baseline value for BP and PR only), and a random cluster effect. Results In 396 children of the EL group who received the PFS treatment, the prevalence of high DA (score ≥ 38) was 18.5%, compared with 24.3% in 391 children of the TSD group (OR = 0.65; 95% confidence interval, 0.46–0.93; P = 0.019). The increases in BP and PR after the PFS were also significantly less in the EL group. Conclusion School-based experiential learning intervention before a dental visit is feasible and effective in reducing children’s dental anxiety during PFS. Trial registration The trial was registered in Chinese Clinical Trial Registry on 5 January 2020 (No.: ChiCTR2000028878, retrospectively registered).

Using transient grating spectroscopy (TGS) we measure the thermal diffusivity of tungsten exposed to different levels of 20 MeV self-ion irradiation. Damage as low as 3.2 x 10^-4 displacements per atom (dpa) causes a measurable reduction in thermal diffusivity. Doses of 0.1 dpa and above, up to 10 dpa, give a degradation of around 55% from the pristine value at room temperature. Using a kinetic theory model, the density of irradiation-induced point defects is estimated based on the measured changes in thermal diffusivity as a function of dose. These predictions are compared with point defect and dislocation loop densities observed in transmission electron microscopy (TEM). Molecular dynamics (MD) predictions are combined with the TEM observations to estimate the density of point defects associated with defect clusters too small to be probed by TEM. When these "invisible" defects are accounted for, the total point defect density agrees well with that estimated from TGS for a range of doses spanning 3 orders of magnitude. Kinetic theory modelling is also used to estimate the thermal diffusivity degradation expected due to TEM-visible and invisible defects. Finely distributed invisible defects appear to play a much more important role in the thermal diffusivity reduction than larger TEM-visible dislocation loops. This work demonstrates the capability of TGS, in conjunction with kinetic theory models, to provide rapid, quantitative insight into defect densities and property evolution in irradiated materials., The following article has been revised and submitted to Acta Materialia. After it is published, it will be found at https://www.journals.elsevier.com/acta-materialia

Developing a comprehensive understanding of the modification of material properties by neutron irradiation is important for the design of future fission and fusion power reactors. Self-ion implantation is commonly used to mimic neutron irradiation damage, however an interesting question concerns the effect of ion energy on the resulting damage structures. The reduction in the thickness of the implanted layer as the implantation energy is reduced results in the significant quandary: Does one attempt to match the primary knock-on atom energy produced during neutron irradiation or implant at a much higher energy, such that a thicker damage layer is produced? Here we address this question by measuring the full strain tensor for two ion implantation energies, 2 MeV and 20 MeV in self-ion implanted tungsten, a critical material for the first wall and divertor of fusion reactors. A comparison of 2 MeV and 20 MeV implanted samples is shown to result in similar lattice swelling. Multi-reflection Bragg coherent diffractive imaging (MBCDI) shows that implantation induced strain is in fact heterogeneous at the nanoscale, suggesting that there is a non-uniform distribution of defects, an observation that is not fully captured by micro-beam Laue diffraction. At the surface, MBCDI and high-resolution electron back-scattered diffraction (HR-EBSD) strain measurements agree quite well in terms of this clustering/non-uniformity of the strain distribution. However, MBCDI reveals that the heterogeneity at greater depths in the sample is much larger than at the surface. This combination of techniques provides a powerful method for detailed investigation of the microstructural damage caused by ion bombardment, and more generally of strain related phenomena in microvolumes that are inaccessible via any other technique., Comment: Please refer to the supplementary information and movies SM1-3 for data visualisation

The microstructure of the surface oxide film formed on an Fe-9Cr Ferritic-Martensitic (F-M) steel after exposure to deaerated high-temperature steam at 600°C for 100 h has been analyzed in detail by advanced characterization techniques. The surface oxide film has been revealed to have a triplex structure, including an outer oxide layer, an inner oxide layer, and an internal oxide layer. Although the outer and inner oxide layers are continuous, the internal oxide layer has been proved to consist of interconnected metallic and chromite phases, which is a typical feature of internal oxidation. The formation mechanisms of each layer have been discussed, finding that, contrary to what the available space model suggests, an external oxidation is not the controlling oxidation mechanism of F-M steels in high-temperature steam. The higher resolution used in this study confirms that the controlling mechanism is internal oxidation.

Displacive transformations have been widely reported in metals, alloys and ceramics, but rarely reported to be important in the aqueous corrosion of alloys. We report here our analysis of the formation of the hexagonal-ZrO suboxide during the aqueous corrosion of α-Zr alloys and propose this to be a paraequilibrium displacive transformation with the rate controlled by oxygen diffusion. Two orientation relationships were identified between α-Zr and hexagonal-ZrO, ( 0002 ) α − Z r ∥ ( 1 ¯ 011 ) h − Z r O and [ 2 ¯ 110 ] α − Z r ∥ [ 10 1 ¯ 2 ] h − Z r O or ( 0002 ) α − Z r ∥ ( 22 4 ¯ 1 ¯ ) h − Z r O and [ 2 ¯ 110 ] α − Z r ∥ [ 1 1 ¯ 01 ] h − Z r O , with the first one more commonly observed. No specific orientation relationships between either hexagonal-ZrO and monoclinic-ZrO2 or α-Zr and monoclinic-ZrO2 were identified, which suggests that the formation of often-reported bulk oxide texture during aqueous corrosion is not related directly to the texture of the metallic substrate. These results provide a guideline for understanding the mechanisms of crystallographic evolution during oxide growth on commercial zirconium alloys, and also demonstrate the capability of transmission Kikuchi diffraction to investigate orientation relationships in nano-scale materials.

Existing multi-label medical image learning tasks generally contain rich relationship information among pathologies such as label co-occurrence and interdependency, which is of great importance for assisting in clinical diagnosis and can be represented as the graph-structured data. However, most state-of-the-art works only focus on regression from the input to the binary labels, failing to make full use of such valuable graph-structured information due to the complexity of graph data. In this paper, we propose a novel label co-occurrence learning framework based on Graph Convolution Networks (GCNs) to explicitly explore the dependencies between pathologies for the multi-label chest X-ray (CXR) image classification task, which we term the “CheXGCN”. Specifically, the proposed CheXGCN consists of two modules, i.e., the image feature embedding (IFE) module and label co-occurrence learning (LCL) module. Thanks to the LCL model, the relationship between pathologies is generalized into a set of classifier scores by introducing the word embedding of pathologies and multi-layer graph information propagation. During end-to-end training, it can be flexibly integrated into the IFE module and then adaptively recalibrate multi-label outputs with these scores. Extensive experiments on the ChestX-Ray14 and CheXpert datasets have demonstrated the effectiveness of CheXGCN as compared with the state-of-the-art baselines.

Morphology and facet engineering have been proved efficient strategies to prepare high-performance photoelectrochemical (PEC) materials. WO3/BiVO4 heterojunction photoanodes with different morphologies were prepared by simply controlling the amount of electrodeposited charge. The coral-like WO3/BiVO4 photoanode with the orientation growth of {110} and {011} active facets of BiVO4 exhibited the optimal PEC performance due to significantly enhanced separation and transfer of photogenerated charge carriers, while the exposure of {−121} facets showed negative effects. 4.71 mA·cm−2 and 2.9 mA·cm−2 of photocurrent densities were obtained for sulfite and water oxidation, respectively, superior to most reported results. Subsequently, a photoelectrochemical-chlorine (PEC-Cl) system was constructed for antibiotic wastewater detoxification with hydrogen recovery. The analysis results indicated that the system can quickly and effectively remove sulfamethoxazole and reduce its toxicity concurrent with high hydrogen yield. The reactive chlorine species (RCS), especially Cl2·− and ClO·, dominated the sulfamethoxazole removal. Possible degradation pathways of sulfamethoxazole were also elucidated.

A novel S-scheme photocatalytic heterojunction composite nanomaterial is developed by integrating zero-dimensional WO3 quantum dots (WQDs) on two-dimensional ultrathin CdIn2S4 (CIS) nanosheets with the aim of fostering carrier separation, enhancing the performance of carrier interface transport, minimizing carrier distance transport, and achieving effective photocatalytic CO2 reduction. The composite photocatalyst WQDs/CdIn2S4 (WCIS) allows for the efficient photocatalytic reduction of CO2 to CO and CH4, as shown by product analysis and isotopic measurement. The photogenerated electrons in WQDs recombine with the holes in CIS nanosheets, and the left electrons in CIS have stronger CO2 reduction abilities. The highest yields of CO and CH4 achieved with the WCIS photocatalyst are 8.2 and 1.6 μmol g-1h−1 ––2.6 and 8 times higher than those for CIS, respectively. Moreover, the S-scheme WCIS possesses a stable crystal structure and recycling ability. Finally, the S-scheme charge transfer path on the WCIS composite is proposed according to theoretical calculation, in-situ irradiated X-ray photoelectron spectroscopy, and electron paramagnetic resonance (ESR) analyses.

In-situ electrocatalytic flue gas desulfurization (FGD) using a carbon black (CB)-based gas diffusion electrode (GDE) is efficient with no secondary pollution. However, higher desulfurization efficiency and energy conservation are demanded. In this work, CB-based GDEs were modified with poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate)-multi-walled carbon nanotubes (PEDOT: PSS-MWCNTs) for H2O2 production from two-electron oxygen reduction reaction (2e-ORR) during in-situ FGD. The results showed that the GDE modified with 100 mg 5% PEDOT: PSS-MWCNTs obtained the highest desulfurization efficiency (100.0%) and the lowest energy consumption (1.07 kW h kg−1), as 2e-ORR efficiency is improved from balancing ORR catalysis, pore structure, hydrophilicity, conductivity of the GDE, and the noncovalent interaction between MWCNTs and PEDOT: PSS. While excess PEDOT: PSS in the PEDOT: PSS-MWCNTs composite would cause reduced total pore area and porosity and excessive hydrophily which is harmful to O2 transfer for the GDE, hindering the 2e-ORR and desulfurization. This compact in-situ FGD system has advantages in desulfurization efficiency, energy consumption and durability, showing great potential in future industrial application.

Cr-coatings processed for different times were synthesized on the surface of AISI 5140 steel by double glow plasma surface alloying (DGPSA). The microstructures, microchemistry and phases of the coating were characterized by backscattering electron imaging (BSEI), energy dispersive spectrometry (EDS), and X-ray diffraction (XRD). The results show that the Cr-coating prepared by DGPSA consists of three layers: a deposited-layer, a diffusion-layer and an affected-layer. With increasing DGPSA processing time, the relative thickness, microstructure and phase composition of the three layers vary greatly. The deposited-layer is mainly composed of pure-Cr, the diffusion-layer consists of Cr-Fe solid solution (Cr-Fe SS) and/or Cr-Fe intermetallic compound (Cr-Fe IMs), while the affected-layer is composed of high-Cr pearlite. After depositing Cr by DGPSA, the corrosion potential is improved and the corrosion current is reduced. Subsequent annealing not only promotes the precipitation of the multiple carbides particles within the pure-Cr coating, but also promotes the transformation of Cr-Fe IMs into Cr-Fe SS. However, these changes have little effect on the hardness and corrosion resistance of the coatings. Keywords: Double glow plasma surface alloying, Chromizing, Hardness, Corrosion resistance, Annealing

Coupled electrochemical system (CES) for electroreduction of CO2 and simultaneous degradation of organic pollutants is a promising CO2 conversion method. However, its performance is severely restrained by insufficient reactants and low electroactive surface areas on the cathode material. Here, a series of novel Sn-based carbon nanotubes (CNTs)/carbon black hybrid gas diffusion electrodes (CNTx/ESGDEs) were fabricated and used as cathodes to enhance the performance of the CES with methyl orange (MO) as a target pollutant. The results show that at an appropriate content of CNTs, the CNTx/ESGDEs offered increased total pore area, porosity, electroactive surface area, and decreased charge transfer resistances. The current density, Faraday efficiency, formic acid production rate, MO removal efficiency, and COD removal efficiency were improved by 140%, 92%, 404%, 76%, and 131%, respectively, at 40 wt% CNTs probably due to enhancement in the electroactive surface area as well as reactant transfer. This study benefits the large-scale applications of CES.

Contemporary semiotics proceeds and progresses along two major paths of human intellectual inquiry in general: One is to constantly extend and deepen social studies; the other is to use theoretical and logical reasoning to examine and even predict the laws of nature and the universe. To highlight these two paths and reflect the latest trends in current semiotic inquiry, we have launched the book series of “Select Works of Eminent Contemporary Semioticians,” published by the Nanjing Normal University Press. The first five English monographs included in this book series are Basics of semiotics (eighth expanded edition) and Logic as a liberal art by John Deely, Marshall McLuhan: The unwitting semiotician by Marcel Danesi, Signs in society and culture by Arthur Asa Berger, and The way of logic by Christopher S. Morrissey. These five books afford not only revelations in the ways of knowing and the dimensions of thought, but also new perspectives for interpreting contemporary sociocultural phenomena and their developments.

SLC26A3 encodes a Cl-/HCO3- ion transporter that is also known as downregulated in adenoma (DRA) and is involved in HCO3-/mucus formation. The role of DRA in the epithelial barrier has not been previously established. In this study, we investigated the in vivo and in vitro mechanisms of DRA in the colon epithelial barrier. Immunofluorescence (IF) and co-immunoprecipitation (co-IP) studies reveal that DRA binds directly to tight junction (TJ) proteins and affects the expression of TJ proteins in polarized Caco-2BBe cells. Similarly, DRA colocalizes with ZO-1 in the intestinal epithelium. Knockdown or overexpression of DRA leads to alterations in TJ proteins and epithelial permeability. In addition, TNF-α treatment downregulates DRA by activating NF-кB and subsequently affecting intestinal epithelial barrier integrity. Furthermore, overexpression of DRA partly reverses the TNF-α-induced damage by stabilizing TJ proteins. Neutralization of TNF-α in dextran sulfate sodium (DSS)-induced colitis mice demonstrates improved the outcomes, and the therapeutic effect of the TNF-α neutralizing mAb is mediated in part by the preservation of DRA expression. These data suggest that DRA may be one of the therapeutic targets of TNF-α. Moreover, DRA delivered by adenovirus vector significantly prevents the exacerbation of colitis and improves epithelial barrier function by promoting the recovery of TJ proteins in DSS-treated mice. In conclusion, DRA plays a role in protecting the epithelial barrier and may be a therapeutic target in gut homeostasis.

Using bibliometric analysis combined with information visualization analysis, this paper aims at investigating the global characteristics and trends of research on ceramic membranes. According to the 3697 publications from 1998 to 2016 in Science Citation Index Expended, this study was conducted from five major aspects, including basic growth trends analysis, countries/ territories and institutions analysis, categories and journals analysis, keywords analysis, and citation bursts detection. This study revealed positive growth trends of the research on ceramic membranes. The most productive countries and institutions were both from Peoples R China, and the collaborations among countries and institutions were frequent worldwide. The result of categories analysis revealed that the major discipline groups of the research on ceramic membranes were distributed in chemistry, physics, material, and application. Water resource, energy, environmental science and food engineering were the main application fields of ceramic membranes according to the journals analysis. Furthermore, three keyword clusters were identified, indicating that the main research directions of the research on ceramic membranes included membrane filtration, oxygen permeation and the fabrication of ceramic membranes. Finally, the top 20 citation bursts with the maximum burst strength were detected, indicating that the research on oxygen separation and water treatment has been flourishing in recent years.

Converting austenite to martensite is a very effective and low-cost strategy for steel strengthening, but it results in a significant loss of ductility. In this study, we propose a novel method which simultaneously strengthens and toughens austenitic steels by introducing a gradient of martensite phase. We find that a gradient of deformation-induced martensite (α′-M) particles, with a volume fraction increasing from core to surface can be obtained in cylindrical AISI 304 stainless steel (304 SS) rods by applying free-end-torsion (FET). We compared the microstructures and tensile properties of gradient-structured 304 SS prepared by unidirectional-torsion (UT) and cyclic forward/reverse torsion (CFRT). It appears that piled-up dislocations formed near the core region during FET processing play a key role in the subsequent tensile deformation, and control the strain-hardening ability of the FET treated samples. The gradient α′-M enhances the strength of the surface layer and improves the tensile properties of the FET treated samples as a whole. Compared to UT, CFRT is more effective in inducing martensitic transformation, and enhances the gradient distribution of the α′-M. These findings provide a pathway for developing high strength and good ductility steels and other alloyed metals via gradient distributed second phase particles. Keywords: Gradient-structured metals, Gradient martensite, Torsion, Deformation-induced martensite, Mechanical properties

Rapid development of industrial production has stimulated the growth of consumption of raw and auxiliary materials including organic paints, among which volatile organic compounds (VOCs) are proved harmful to the population who inhale the polluted air based on epidemiologic studies. Therefore, new types of environment-friendly paints were developed to replace solvent-based paints (SBPs). Nevertheless, new types of paints containing VOCs failed to replace SBPs entirely due to certain disadvantages. Hence, five kinds of paints were employed in simulation experiments to assess the health risk of primary receptor including three kinds of water-based paints (WBPs) and two kinds of SBPs. Conclusions showed that mean TVOC concentration in breathing zone of primary receptor ranged from 9.5 to 13.6 mg/m3 and 3.4 × 103 to 1.4 × 104 mg/m3 for WBPs and SBPs, respectively. Assessments of non-cancer risk concluded that nearly one third quantified compounds exceeded corresponding thresholds for WBPs, and the maximum risk value was 101.33; for SBPs, the maximum risk value reached 50760.20, and twenty-two compounds exceeded the reference limits. The calculation of cancer risk values showed that seventeen compounds were higher than acceptable limit amongst which 1,2-dibromoethane had maximum values of 1.27 × 10−2 to 3.24 × 10−2 for WBPs; for SBPs, all quantified compounds exceeded the acceptable limit, and 82.61% VOCs were distributed in a scope larger than 1 × 10−3. Additionally, a removal efficiency of 60% was considered for primary receptor with personal protective equipment, and subsequent results confirmed its inability of lowering the risk resulted from hazardous VOCs. The calculated potential health risk could be applied to estimate the total health risk for both primary and secondary receptor based on consumed materials. The finding suggested that WBPs could improve VOCs exposure condition and reduce the direct and potential health risk significantly for primary receptor, although they might dissatisfy acceptable limit.

This article presents a novel quasi in-situ analysis, which allowed for examining the same microstructural area before and after irradiation, in two distinct facilities. One facility is used for the irradiation, and one for the energy dispersive X-ray spectroscopy (EDX) in a transmission electron microscope (TEM). The material studied is an austenitic oxide dispersion strengthened (ODS) stainless steel, modeled after commercial grade 310 L (25Cr 20Ni 2Mo-0.02C-0.4N-0.35Y2O3-0.5Ti-bal.Fe), which is synthesized from a powder metallurgy fabrication route using hot isostatic pressing. ODS materials are suitable for applications in: structural, highly corrosive, nuclear, and electromagnetic field environments. In fact, new generation fusion systems represent all four of these demands at the same time. The 310-ODS material is irradiated to ∼1.5dpa at 520OC with 1 MeV Kr2+ 7.5 × 1014 ions cm−2 (∼1.25 × 10−3 dpa/s). Quasi in-situ EDX line scans are presented, focusing on the interactions of: Fe, Cr, Ni, Y, Ti, and O. The examined particles are two Ti-rich structures, which present themselves as non-stoichiometric oxides (>200 nm) embedded within the iron matrix. The Y/Ti at% ratios in both observed particles decreased slightly from 0.34 ± 0.07 and 0.28 ± 0.04, to 0.26 ± 0.08 and 0.20 ± 0.06 respectively, suggesting a dissolution mechanism has initiated under this irradiation condition. It is often a question of dissolution vs. amorphization in these materials. Included is a detailed discussion of these two mechanisms as a function of temperature, fluence, and irradiating energy, with contrast to the current literature. Furthermore, attached is a data-in-brief (DiB), which includes the EDX spectrum and raw data captured from the experiment.

A novel kind of Z-scheme ternary heterojunctions phosphate-doped BiVO4/graphene quantum dots/P-doped g-C3N4 (BVP/GQDs/PCN) were fabricated for the visible light degradation of norfloxacin (NOR), a typical antibiotic. Compared with binary type-II heterojunction phosphate-doped BiVO4/PCN (BVP/PCN), Z-scheme BVP/GQDs/PCN exhibited promoted interfacial charge transfer efficiency and broadened visible light response range, endowing them with excellent photodegradation activity and mineralization ability in NOR degradation. A high NOR degradation rate of 86.3% with a removal rate of total organic carbon (TOC) of 55.8% can be achieved over BVP/GQDs/PCN for 120 min visible light irradiation, which is an excellent performance compared with ever reported similar photocatalysts. In particular, because of the enhanced redox ability of photogenerated charges and the generation of multiple active species (eg. OH and O2−) over Z-scheme photocatalytic system, the accumulation of highly toxic degradation intermediates was greatly inhibited, and a better detoxication performance was obtained compared to PCN and BVP/PCN. This work may shed light on the inhibition of highly toxic degradation intermediates of antibiotics by regulating the charge transfer mechanism, photocatalytic active species, and the degradation pathway of antibiotics.

This study explored and compared the influence of graphite, graphene, and graphene oxide (GO) on the performance of anaerobic co-digestion fed with sewage sludge and food waste, the variations of antibiotic resistance genes (ARGs), and the evolution of microbial community. Graphene exhibited the best performance for improving methane production and organic degradation, which increased by 36.09% and 23.07% compared with control group. The experimental results showed that graphene had the greatest influence on the removal efficiency of blaOXA-1, macrolide resistance genes (ermF and ermB), and some tetracycline resistance genes (tetQ and tetX); however, the removal efficiency of sulfonamide resistance genes (sul1 and sul2), intI1, and some tetracycline resistance genes (tetM, tetO, and tetW) were highest when GO was added. Network analysis indicated that the host cells of mefA, ermB, and tetO were different from other ARG host cells; moreover, graphene controlled the horizontal transfer of ARGs between microbial communities.

Hemicellulose is one of the main components of lignocellulose, and xylan and xylose are polysaccharides and monosaccharides that account for a high proportion of hemicellulose separation and depolymerization products. As a derivative of the above three substances, Furfural (FF) is a green platform compound prepared from renewable biomass raw materials and has broad application prospects. Based on the furfural production process, we review the conversion mechanism of hemicellulose, xylan and xylose and the role of Bronsted acid and Lewis acid in the reaction system. Meanwhile, the problems to be solved in each production stage are summarized. According to the physical form, homogeneous and heterogeneous catalysts are distinguished in the reaction of preparing furfural with different substrates. For the solvent system, the role and classification of the reaction phase and the extraction phase are reasonably generalized. The development challenges and directions are discussed in depth, and the potential new technologies and new systems that may be used in the furfural industrial production process are proposed.